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Chat with C# and ASP.NET MVC

(warning)

Warning

As the Programmable Chat API is set to sunset in 2022, we will no longer maintain these chat tutorials.

Please see our Conversations API QuickStart to start building robust virtual spaces for conversation.

(error)

Danger

Programmable Chat has been deprecated and is no longer supported. Instead, we'll be focusing on the next generation of chat: Twilio Conversations. Find out more about the EOL process here.

If you're starting a new project, please visit the Conversations Docs to begin. If you've already built on Programmable Chat, please visit our Migration Guide to learn about how to switch.

Ready to implement a chat application using Twilio Chat?

This application allows users to exchange messages through different channels, using the Twilio Chat API. With this example, we'll show you how to use this API to manage channels and their usages.

Properati built a web and mobile messaging app to help real estate buyers and sellers connect in real time. Learn more here.

For your convenience, we consolidated the source code for this tutorial in a single GitHub repository. Feel free to clone it and tweak as required.

Token Generation

In order to create a Twilio Chat client, you will need an access token. This token provides access for a client (such as a Javascript front end web application) to talk to the Twilio Chat API.

We generate this token by creating a new Token and providing it with a ChatGrant. With the Token at hand, we can use its method ToJwt() to return its string representation.

Generate an Access Token

TwilioChat.Web/Domain/TokenGenerator.cs


_30using System.Collections.Generic;
_30using Twilio.Jwt.AccessToken;
_30
_30namespace TwilioChat.Web.Domain
_30{
_30    public interface ITokenGenerator
_30    {
_30        string Generate(string identity);
_30    }
_30
_30    public class TokenGenerator : ITokenGenerator
_30    {
_30        public string Generate(string identity)
_30        {
_30            var grants = new HashSet<IGrant>
_30            {
_30                new ChatGrant {ServiceSid = Configuration.ChatServiceSID}
_30            };
_30
_30            var token = new Token(
_30                Configuration.AccountSID,
_30                Configuration.ApiKey,
_30                Configuration.ApiSecret,
_30                identity,
_30                grants: grants);
_30
_30            return token.ToJwt();
_30        }
_30    }
_30}

We can generate a token, now we need a way for the chat app to get it.

Token Generation Controller

On our controller we expose an endpoint that provides a valid token. Using the parameter:

identity : identifies the user itself.

It uses tokenGenerator.Generate method to get hold of a new token and return it in a JSON format to be used for our client.

Token Generation Controller

TwilioChat.Web/Controllers/TokenController.cs


_27using System.Web.Mvc;
_27using TwilioChat.Web.Domain;
_27
_27namespace TwilioChat.Web.Controllers
_27{
_27    public class TokenController : Controller
_27    {
_27        private readonly ITokenGenerator _tokenGenerator;
_27
_27        public TokenController() : this(new TokenGenerator()) { }
_27
_27        public TokenController(ITokenGenerator tokenGenerator)
_27        {
_27            _tokenGenerator = tokenGenerator;
_27        }
_27
_27        // POST: Token
_27        [HttpPost]
_27        public ActionResult Index(string identity)
_27        {
_27            if (identity == null) return null;
_27
_27            var token = _tokenGenerator.Generate(identity);
_27            return Json(new {identity, token});
_27        }
_27    }
_27}

Now that we have a route that generates JWT tokens on demand, let's use this route to initialize our Twilio Chat Client.

Initialize the Chat Client

On our client, we fetch a new Token using a POST request to our endpoint.

And with the token we can instantiate a new Twilio.AccessManager that is used to initialize our Twilio.Chat.Client.

Initialize the Chat Client

Twilio Chat Client Initialization in JS


_381var twiliochat = (function () {
_381    var tc = {};
_381
_381    var GENERAL_CHANNEL_UNIQUE_NAME = 'general';
_381    var GENERAL_CHANNEL_NAME = 'General Channel';
_381    var MESSAGES_HISTORY_LIMIT = 50;
_381
_381    var $channelList;
_381    var $inputText;
_381    var $usernameInput;
_381    var $statusRow;
_381    var $connectPanel;
_381    var $newChannelInputRow;
_381    var $newChannelInput;
_381    var $typingRow;
_381    var $typingPlaceholder;
_381
_381    $(document).ready(function () {
_381        tc.init();
_381    });
_381
_381    tc.init = function () {
_381        tc.$messageList = $('#message-list');
_381        $channelList = $('#channel-list');
_381        $inputText = $('#input-text');
_381        $usernameInput = $('#username-input');
_381        $statusRow = $('#status-row');
_381        $connectPanel = $('#connect-panel');
_381        $newChannelInputRow = $('#new-channel-input-row');
_381        $newChannelInput = $('#new-channel-input');
_381        $typingRow = $('#typing-row');
_381        $typingPlaceholder = $('#typing-placeholder');
_381        $usernameInput.focus();
_381        $usernameInput.on('keypress', handleUsernameInputKeypress);
_381        $inputText.on('keypress', handleInputTextKeypress);
_381        $newChannelInput.on('keypress', tc.handleNewChannelInputKeypress);
_381        $('#connect-image').on('click', connectClientWithUsername);
_381        $('#add-channel-image').on('click', showAddChannelInput);
_381        $('#leave-span').on('click', disconnectClient);
_381        $('#delete-channel-span').on('click', deleteCurrentChannel);
_381    };
_381
_381    function handleUsernameInputKeypress(event) {
_381        if (event.keyCode === 13) {
_381            connectClientWithUsername();
_381        }
_381    }
_381
_381    function handleInputTextKeypress(event) {
_381        if (event.keyCode === 13) {
_381            tc.currentChannel.sendMessage($(this).val());
_381            event.preventDefault();
_381            $(this).val('');
_381        }
_381        else {
_381            notifyTyping();
_381        }
_381    }
_381
_381    var notifyTyping = $.throttle(function () {
_381        tc.currentChannel.typing();
_381    }, 1000);
_381
_381    tc.handleNewChannelInputKeypress = function (event) {
_381        if (event.keyCode === 13) {
_381            tc.messagingClient
_381                .createChannel({
_381                    friendlyName: $newChannelInput.val(),
_381                })
_381                .then(hideAddChannelInput);
_381
_381            $(this).val('');
_381            event.preventDefault();
_381        }
_381    };
_381
_381    function connectClientWithUsername() {
_381        var usernameText = $usernameInput.val();
_381        $usernameInput.val('');
_381        if (usernameText == '') {
_381            alert('Username cannot be empty');
_381            return;
_381        }
_381        tc.username = usernameText;
_381        fetchAccessToken(tc.username, connectMessagingClient);
_381    }
_381
_381    function fetchAccessToken(username, handler) {
_381        $.post('/token', { identity: username}, null, 'json')
_381            .done(function (response) {
_381                handler(response.token);
_381            })
_381            .fail(function (error) {
_381                console.log('Failed to fetch the Access Token with error: ' + error);
_381            });
_381    }
_381
_381    function connectMessagingClient(token) {
_381        // Initialize the Chat messaging client
_381        Twilio.Chat.Client.create(token).then(function (client) {
_381            tc.messagingClient = client;
_381            updateConnectedUI();
_381            tc.loadChannelList(tc.joinGeneralChannel);
_381            tc.messagingClient.on('channelAdded', $.throttle(tc.loadChannelList));
_381            tc.messagingClient.on('channelRemoved', $.throttle(tc.loadChannelList));
_381            tc.messagingClient.on('tokenExpired', refreshToken);
_381        });
_381    }
_381
_381    function refreshToken() {
_381        fetchAccessToken(tc.username, setNewToken);
_381    }
_381
_381    function setNewToken(token) {
_381        tc.messagingClient.updateToken(token);
_381    }
_381
_381    function updateConnectedUI() {
_381        $('#username-span').text(tc.username);
_381        $statusRow.addClass('connected').removeClass('disconnected');
_381        tc.$messageList.addClass('connected').removeClass('disconnected');
_381        $connectPanel.addClass('connected').removeClass('disconnected');
_381        $inputText.addClass('with-shadow');
_381        $typingRow.addClass('connected').removeClass('disconnected');
_381    }
_381
_381    tc.loadChannelList = function (handler) {
_381        if (tc.messagingClient === undefined) {
_381            console.log('Client is not initialized');
_381            return;
_381        }
_381
_381        tc.messagingClient.getPublicChannelDescriptors().then(function (channels) {
_381            tc.channelArray = tc.sortChannelsByName(channels.items);
_381            $channelList.text('');
_381            tc.channelArray.forEach(addChannel);
_381            if (typeof handler === 'function') {
_381                handler();
_381            }
_381        });
_381    };
_381
_381    tc.joinGeneralChannel = function () {
_381        console.log('Attempting to join "general" chat channel...');
_381        if (!tc.generalChannel) {
_381            // If it doesn't exist, let's create it
_381            tc.messagingClient.createChannel({
_381                uniqueName: GENERAL_CHANNEL_UNIQUE_NAME,
_381                friendlyName: GENERAL_CHANNEL_NAME
_381            }).then(function (channel) {
_381                console.log('Created general channel');
_381                tc.generalChannel = channel;
_381                tc.loadChannelList(tc.joinGeneralChannel);
_381            });
_381        }
_381        else {
_381            console.log('Found general channel:');
_381            setupChannel(tc.generalChannel);
_381        }
_381    };
_381
_381    function initChannel(channel) {
_381        console.log('Initialized channel ' + channel.friendlyName);
_381        return tc.messagingClient.getChannelBySid(channel.sid);
_381    }
_381
_381    function joinChannel(_channel) {
_381        return _channel.join()
_381            .then(function (joinedChannel) {
_381                console.log('Joined channel ' + joinedChannel.friendlyName);
_381                updateChannelUI(_channel);
_381
_381                return joinedChannel;
_381            })
_381            .catch(function (err) {
_381                if (_channel.status == 'joined') {
_381                    updateChannelUI(_channel);
_381                    return _channel;
_381                }
_381                console.error(
_381                    "Couldn't join channel " + _channel.friendlyName + ' because -> ' + err
_381                );
_381            });
_381    }
_381
_381    function initChannelEvents() {
_381        console.log(tc.currentChannel.friendlyName + ' ready.');
_381        tc.currentChannel.on('messageAdded', tc.addMessageToList);
_381        tc.currentChannel.on('typingStarted', showTypingStarted);
_381        tc.currentChannel.on('typingEnded', hideTypingStarted);
_381        tc.currentChannel.on('memberJoined', notifyMemberJoined);
_381        tc.currentChannel.on('memberLeft', notifyMemberLeft);
_381        $inputText.prop('disabled', false).focus();
_381    }
_381
_381    function setupChannel(channel) {
_381        return leaveCurrentChannel()
_381            .then(function () {
_381                return initChannel(channel);
_381            })
_381            .then(function (_channel) {
_381                return joinChannel(_channel);
_381            })
_381            .then(initChannelEvents);
_381    }
_381
_381    tc.loadMessages = function () {
_381        tc.currentChannel.getMessages(MESSAGES_HISTORY_LIMIT).then(function (messages) {
_381            messages.items.forEach(tc.addMessageToList);
_381        });
_381    };
_381
_381    function leaveCurrentChannel() {
_381        if (tc.currentChannel) {
_381            return tc.currentChannel.leave().then(function (leftChannel) {
_381                console.log('left ' + leftChannel.friendlyName);
_381                leftChannel.removeListener('messageAdded', tc.addMessageToList);
_381                leftChannel.removeListener('typingStarted', showTypingStarted);
_381                leftChannel.removeListener('typingEnded', hideTypingStarted);
_381                leftChannel.removeListener('memberJoined', notifyMemberJoined);
_381                leftChannel.removeListener('memberLeft', notifyMemberLeft);
_381            });
_381        } else {
_381            return Promise.resolve();
_381        }
_381    }
_381
_381    tc.addMessageToList = function (message) {
_381        var rowDiv = $('<div>').addClass('row no-margin');
_381        rowDiv.loadTemplate($('#message-template'), {
_381            username: message.author,
_381            date: dateFormatter.getTodayDate(message.dateCreated),
_381            body: message.body
_381        });
_381        if (message.author === tc.username) {
_381            rowDiv.addClass('own-message');
_381        }
_381
_381        tc.$messageList.append(rowDiv);
_381        scrollToMessageListBottom();
_381    };
_381
_381    function notifyMemberJoined(member) {
_381        notify(member.identity + ' joined the channel')
_381    }
_381
_381    function notifyMemberLeft(member) {
_381        notify(member.identity + ' left the channel');
_381    }
_381
_381    function notify(message) {
_381        var row = $('<div>').addClass('col-md-12');
_381        row.loadTemplate('#member-notification-template', {
_381            status: message
_381        });
_381        tc.$messageList.append(row);
_381        scrollToMessageListBottom();
_381    }
_381
_381    function showTypingStarted(member) {
_381        $typingPlaceholder.text(member.identity + ' is typing...');
_381    }
_381
_381    function hideTypingStarted(member) {
_381        $typingPlaceholder.text('');
_381    }
_381
_381    function scrollToMessageListBottom() {
_381        tc.$messageList.scrollTop(tc.$messageList[0].scrollHeight);
_381    }
_381
_381    function updateChannelUI(selectedChannel) {
_381        var channelElements = $('.channel-element').toArray();
_381        var channelElement = channelElements.filter(function (element) {
_381            return $(element).data().sid === selectedChannel.sid;
_381        });
_381        channelElement = $(channelElement);
_381        if (tc.currentChannelContainer === undefined && selectedChannel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_381            tc.currentChannelContainer = channelElement;
_381        }
_381        tc.currentChannelContainer.removeClass('selected-channel').addClass('unselected-channel');
_381        channelElement.removeClass('unselected-channel').addClass('selected-channel');
_381        tc.currentChannelContainer = channelElement;
_381        tc.currentChannel = selectedChannel;
_381        tc.loadMessages();
_381    }
_381
_381    function showAddChannelInput() {
_381        if (tc.messagingClient) {
_381            $newChannelInputRow.addClass('showing').removeClass('not-showing');
_381            $channelList.addClass('showing').removeClass('not-showing');
_381            $newChannelInput.focus();
_381        }
_381    }
_381
_381    function hideAddChannelInput() {
_381        $newChannelInputRow.addClass('not-showing').removeClass('showing');
_381        $channelList.addClass('not-showing').removeClass('showing');
_381        $newChannelInput.val('');
_381    }
_381
_381    function addChannel(channel) {
_381        if (channel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_381            tc.generalChannel = channel;
_381        }
_381        var rowDiv = $('<div>').addClass('row channel-row');
_381        rowDiv.loadTemplate('#channel-template', {
_381            channelName: channel.friendlyName
_381        });
_381
_381        var channelP = rowDiv.children().children().first();
_381
_381        rowDiv.on('click', selectChannel);
_381        channelP.data('sid', channel.sid);
_381        if (tc.currentChannel && channel.sid === tc.currentChannel.sid) {
_381            tc.currentChannelContainer = channelP;
_381            channelP.addClass('selected-channel');
_381        }
_381        else {
_381            channelP.addClass('unselected-channel')
_381        }
_381
_381        $channelList.append(rowDiv);
_381    }
_381
_381    function deleteCurrentChannel() {
_381        if (!tc.currentChannel) {
_381            return;
_381        }
_381
_381        if (tc.currentChannel.sid === tc.generalChannel.sid) {
_381            alert('You cannot delete the general channel');
_381            return;
_381        }
_381
_381        tc.currentChannel
_381            .delete()
_381            .then(function (channel) {
_381                console.log('channel: ' + channel.friendlyName + ' deleted');
_381                setupChannel(tc.generalChannel);
_381            });
_381    }
_381
_381    function selectChannel(event) {
_381        var target = $(event.target);
_381        var channelSid = target.data().sid;
_381        var selectedChannel = tc.channelArray.filter(function (channel) {
_381            return channel.sid === channelSid;
_381        })[0];
_381        if (selectedChannel === tc.currentChannel) {
_381            return;
_381        }
_381        setupChannel(selectedChannel);
_381    };
_381
_381    function disconnectClient() {
_381        leaveCurrentChannel();
_381        $channelList.text('');
_381        tc.$messageList.text('');
_381        channels = undefined;
_381        $statusRow.addClass('disconnected').removeClass('connected');
_381        tc.$messageList.addClass('disconnected').removeClass('connected');
_381        $connectPanel.addClass('disconnected').removeClass('connected');
_381        $inputText.removeClass('with-shadow');
_381        $typingRow.addClass('disconnected').removeClass('connected');
_381    }
_381
_381    tc.sortChannelsByName = function (channels) {
_381        return channels.sort(function (a, b) {
_381            if (a.friendlyName === GENERAL_CHANNEL_NAME) {
_381                return -1;
_381            }
_381            if (b.friendlyName === GENERAL_CHANNEL_NAME) {
_381                return 1;
_381            }
_381            return a.friendlyName.localeCompare(b.friendlyName);
_381        });
_381    };
_381
_381    return tc;
_381})();

Now that we've initialized our Chat Client, let's see how we can get a list of channels.

Get the Channel List

After initializing the client, we can now call it's method getChannels to retrieve all visible channels. The method returns a promise as a result that we use to show the list of channels retrieved on the UI.

Get the Channel List

TwilioChat.Web/Scripts/twiliochat.js


_337var twiliochat = (function () {
_337    var tc = {};
_337
_337    var GENERAL_CHANNEL_UNIQUE_NAME = 'general';
_337    var GENERAL_CHANNEL_NAME = 'General Channel';
_337    var MESSAGES_HISTORY_LIMIT = 50;
_337
_337    var $channelList;
_337    var $inputText;
_337    var $usernameInput;
_337    var $statusRow;
_337    var $connectPanel;
_337    var $newChannelInputRow;
_337    var $newChannelInput;
_337    var $typingRow;
_337    var $typingPlaceholder;
_337
_337    $(document).ready(function () {
_337        tc.$messageList = $('#message-list');
_337        $channelList = $('#channel-list');
_337        $inputText = $('#input-text');
_337        $usernameInput = $('#username-input');
_337        $statusRow = $('#status-row');
_337        $connectPanel = $('#connect-panel');
_337        $newChannelInputRow = $('#new-channel-input-row');
_337        $newChannelInput = $('#new-channel-input');
_337        $typingRow = $('#typing-row');
_337        $typingPlaceholder = $('#typing-placeholder');
_337        $usernameInput.focus();
_337        $usernameInput.on('keypress', handleUsernameInputKeypress);
_337        $inputText.on('keypress', handleInputTextKeypress);
_337        $newChannelInput.on('keypress', tc.handleNewChannelInputKeypress);
_337        $('#connect-image').on('click', connectClientWithUsername);
_337        $('#add-channel-image').on('click', showAddChannelInput);
_337        $('#leave-span').on('click', disconnectClient);
_337        $('#delete-channel-span').on('click', deleteCurrentChannel);
_337    });
_337
_337    function handleUsernameInputKeypress(event) {
_337        if (event.keyCode === 13) {
_337            connectClientWithUsername();
_337        }
_337    }
_337
_337    function handleInputTextKeypress(event) {
_337        if (event.keyCode === 13) {
_337            tc.currentChannel.sendMessage($(this).val());
_337            event.preventDefault();
_337            $(this).val('');
_337        }
_337        else {
_337            notifyTyping();
_337        }
_337    }
_337
_337    var notifyTyping = $.throttle(function () {
_337        tc.currentChannel.typing();
_337    }, 1000);
_337
_337    tc.handleNewChannelInputKeypress = function (event) {
_337        if (event.keyCode === 13) {
_337            tc.messagingClient.createChannel({
_337                friendlyName: $newChannelInput.val()
_337            }).then(hideAddChannelInput);
_337            $(this).val('');
_337            event.preventDefault();
_337        }
_337    };
_337
_337    function connectClientWithUsername() {
_337        var usernameText = $usernameInput.val();
_337        $usernameInput.val('');
_337        if (usernameText == '') {
_337            alert('Username cannot be empty');
_337            return;
_337        }
_337        tc.username = usernameText;
_337        fetchAccessToken(tc.username, connectMessagingClient);
_337    }
_337
_337    function fetchAccessToken(username, handler) {
_337        $.post('/token', {
_337            identity: username,
_337            device: 'browser'
_337        }, function (data) {
_337            handler(data);
_337        }, 'json');
_337    }
_337
_337    function connectMessagingClient(tokenResponse) {
_337        // Initialize the IP messaging client
_337        tc.accessManager = new Twilio.AccessManager(tokenResponse.token);
_337        tc.messagingClient = new Twilio.IPMessaging.Client(tc.accessManager);
_337        updateConnectedUI();
_337        tc.loadChannelList(tc.joinGeneralChannel);
_337        tc.messagingClient.on('channelAdded', $.throttle(tc.loadChannelList));
_337        tc.messagingClient.on('channelRemoved', $.throttle(tc.loadChannelList));
_337        tc.messagingClient.on('tokenExpired', refreshToken);
_337    }
_337
_337    function refreshToken() {
_337        fetchAccessToken(tc.username, setNewToken);
_337    }
_337
_337    function setNewToken(tokenResponse) {
_337        tc.accessManager.updateToken(tokenResponse.token);
_337    }
_337
_337    function updateConnectedUI() {
_337        $('#username-span').text(tc.username);
_337        $statusRow.addClass('connected').removeClass('disconnected');
_337        tc.$messageList.addClass('connected').removeClass('disconnected');
_337        $connectPanel.addClass('connected').removeClass('disconnected');
_337        $inputText.addClass('with-shadow');
_337        $typingRow.addClass('connected').removeClass('disconnected');
_337    }
_337
_337    tc.loadChannelList = function (handler) {
_337        if (tc.messagingClient === undefined) {
_337            console.log('Client is not initialized');
_337            return;
_337        }
_337
_337        tc.messagingClient.getChannels().then(function (channels) {
_337            tc.channelArray = tc.sortChannelsByName(channels);
_337            $channelList.text('');
_337            tc.channelArray.forEach(addChannel);
_337            if (typeof handler === 'function') {
_337                handler();
_337            }
_337        });
_337    };
_337
_337    tc.joinGeneralChannel = function () {
_337        console.log('Attempting to join "general" chat channel...');
_337        if (!tc.generalChannel) {
_337            // If it doesn't exist, let's create it
_337            tc.messagingClient.createChannel({
_337                uniqueName: GENERAL_CHANNEL_UNIQUE_NAME,
_337                friendlyName: GENERAL_CHANNEL_NAME
_337            }).then(function (channel) {
_337                console.log('Created general channel');
_337                tc.generalChannel = channel;
_337                tc.loadChannelList(tc.joinGeneralChannel);
_337            });
_337        }
_337        else {
_337            console.log('Found general channel:');
_337            setupChannel(tc.generalChannel);
_337        }
_337    };
_337
_337    function setupChannel(channel) {
_337        // Join the channel
_337        channel.join().then(function (joinedChannel) {
_337            console.log('Joined channel ' + joinedChannel.friendlyName);
_337            leaveCurrentChannel();
_337            updateChannelUI(channel);
_337            tc.currentChannel = channel;
_337            tc.loadMessages();
_337            channel.on('messageAdded', tc.addMessageToList);
_337            channel.on('typingStarted', showTypingStarted);
_337            channel.on('typingEnded', hideTypingStarted);
_337            channel.on('memberJoined', notifyMemberJoined);
_337            channel.on('memberLeft', notifyMemberLeft);
_337            $inputText.prop('disabled', false).focus();
_337            tc.$messageList.text('');
_337        });
_337    }
_337
_337    tc.loadMessages = function () {
_337        tc.currentChannel.getMessages(MESSAGES_HISTORY_LIMIT).then(function (messages) {
_337            messages.forEach(tc.addMessageToList);
_337        });
_337    };
_337
_337    function leaveCurrentChannel() {
_337        if (tc.currentChannel) {
_337            tc.currentChannel.leave().then(function (leftChannel) {
_337                console.log('left ' + leftChannel.friendlyName);
_337                leftChannel.removeListener('messageAdded', tc.addMessageToList);
_337                leftChannel.removeListener('typingStarted', showTypingStarted);
_337                leftChannel.removeListener('typingEnded', hideTypingStarted);
_337                leftChannel.removeListener('memberJoined', notifyMemberJoined);
_337                leftChannel.removeListener('memberLeft', notifyMemberLeft);
_337            });
_337        }
_337    }
_337
_337    tc.addMessageToList = function (message) {
_337        var rowDiv = $('<div>').addClass('row no-margin');
_337        rowDiv.loadTemplate($('#message-template'), {
_337            username: message.author,
_337            date: dateFormatter.getTodayDate(message.timestamp),
_337            body: message.body
_337        });
_337        if (message.author === tc.username) {
_337            rowDiv.addClass('own-message');
_337        }
_337
_337        tc.$messageList.append(rowDiv);
_337        scrollToMessageListBottom();
_337    };
_337
_337    function notifyMemberJoined(member) {
_337        notify(member.identity + ' joined the channel')
_337    }
_337
_337    function notifyMemberLeft(member) {
_337        notify(member.identity + ' left the channel');
_337    }
_337
_337    function notify(message) {
_337        var row = $('<div>').addClass('col-md-12');
_337        row.loadTemplate('#member-notification-template', {
_337            status: message
_337        });
_337        tc.$messageList.append(row);
_337        scrollToMessageListBottom();
_337    }
_337
_337    function showTypingStarted(member) {
_337        $typingPlaceholder.text(member.identity + ' is typing...');
_337    }
_337
_337    function hideTypingStarted(member) {
_337        $typingPlaceholder.text('');
_337    }
_337
_337    function scrollToMessageListBottom() {
_337        tc.$messageList.scrollTop(tc.$messageList[0].scrollHeight);
_337    }
_337
_337    function updateChannelUI(selectedChannel) {
_337        var channelElements = $('.channel-element').toArray();
_337        var channelElement = channelElements.filter(function (element) {
_337            return $(element).data().sid === selectedChannel.sid;
_337        });
_337        channelElement = $(channelElement);
_337        if (tc.currentChannelContainer === undefined && selectedChannel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_337            tc.currentChannelContainer = channelElement;
_337        }
_337        tc.currentChannelContainer.removeClass('selected-channel').addClass('unselected-channel');
_337        channelElement.removeClass('unselected-channel').addClass('selected-channel');
_337        tc.currentChannelContainer = channelElement;
_337    }
_337
_337    function showAddChannelInput() {
_337        if (tc.messagingClient) {
_337            $newChannelInputRow.addClass('showing').removeClass('not-showing');
_337            $channelList.addClass('showing').removeClass('not-showing');
_337            $newChannelInput.focus();
_337        }
_337    }
_337
_337    function hideAddChannelInput() {
_337        $newChannelInputRow.addClass('not-showing').removeClass('showing');
_337        $channelList.addClass('not-showing').removeClass('showing');
_337        $newChannelInput.val('');
_337    }
_337
_337    function addChannel(channel) {
_337        if (channel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_337            tc.generalChannel = channel;
_337        }
_337        var rowDiv = $('<div>').addClass('row channel-row');
_337        rowDiv.loadTemplate('#channel-template', {
_337            channelName: channel.friendlyName
_337        });
_337
_337        var channelP = rowDiv.children().children().first();
_337
_337        rowDiv.on('click', selectChannel);
_337        channelP.data('sid', channel.sid);
_337        if (tc.currentChannel && channel.sid === tc.currentChannel.sid) {
_337            tc.currentChannelContainer = channelP;
_337            channelP.addClass('selected-channel');
_337        }
_337        else {
_337            channelP.addClass('unselected-channel')
_337        }
_337
_337        $channelList.append(rowDiv);
_337    }
_337
_337    function deleteCurrentChannel() {
_337        if (!tc.currentChannel) {
_337            return;
_337        }
_337        if (tc.currentChannel.sid === tc.generalChannel.sid) {
_337            alert('You cannot delete the general channel');
_337            return;
_337        }
_337        tc.currentChannel.delete().then(function (channel) {
_337            console.log('channel: ' + channel.friendlyName + ' deleted');
_337            setupChannel(tc.generalChannel);
_337        });
_337    }
_337
_337    function selectChannel(event) {
_337        var target = $(event.target);
_337        var channelSid = target.data().sid;
_337        var selectedChannel = tc.channelArray.filter(function (channel) {
_337            return channel.sid === channelSid;
_337        })[0];
_337        if (selectedChannel === tc.currentChannel) {
_337            return;
_337        }
_337        setupChannel(selectedChannel);
_337    };
_337
_337    function disconnectClient() {
_337        leaveCurrentChannel();
_337        $channelList.text('');
_337        tc.$messageList.text('');
_337        channels = undefined;
_337        $statusRow.addClass('disconnected').removeClass('connected');
_337        tc.$messageList.addClass('disconnected').removeClass('connected');
_337        $connectPanel.addClass('disconnected').removeClass('connected');
_337        $inputText.removeClass('with-shadow');
_337        $typingRow.addClass('disconnected').removeClass('connected');
_337    }
_337
_337    tc.sortChannelsByName = function (channels) {
_337        return channels.sort(function (a, b) {
_337            if (a.friendlyName === GENERAL_CHANNEL_NAME) {
_337                return -1;
_337            }
_337            if (b.friendlyName === GENERAL_CHANNEL_NAME) {
_337                return 1;
_337            }
_337            return a.friendlyName.localeCompare(b.friendlyName);
_337        });
_337    };
_337
_337    return tc;
_337})();

Next, we need a default channel.

Join the General Channel

This application will try to join a channel called "General Channel" when it starts. If the channel doesn't exist, we'll create one with that name. The scope of this example application will show you how to work only with public channels, but the Chat client allows you to create private channels and handle invitations.

Notice we set a unique name for the general channel as we don't want to create a new general channel every time we start the application.

Join the General Channel

TwilioChat.Web/Scripts/twiliochat.js


_337var twiliochat = (function () {
_337    var tc = {};
_337
_337    var GENERAL_CHANNEL_UNIQUE_NAME = 'general';
_337    var GENERAL_CHANNEL_NAME = 'General Channel';
_337    var MESSAGES_HISTORY_LIMIT = 50;
_337
_337    var $channelList;
_337    var $inputText;
_337    var $usernameInput;
_337    var $statusRow;
_337    var $connectPanel;
_337    var $newChannelInputRow;
_337    var $newChannelInput;
_337    var $typingRow;
_337    var $typingPlaceholder;
_337
_337    $(document).ready(function () {
_337        tc.$messageList = $('#message-list');
_337        $channelList = $('#channel-list');
_337        $inputText = $('#input-text');
_337        $usernameInput = $('#username-input');
_337        $statusRow = $('#status-row');
_337        $connectPanel = $('#connect-panel');
_337        $newChannelInputRow = $('#new-channel-input-row');
_337        $newChannelInput = $('#new-channel-input');
_337        $typingRow = $('#typing-row');
_337        $typingPlaceholder = $('#typing-placeholder');
_337        $usernameInput.focus();
_337        $usernameInput.on('keypress', handleUsernameInputKeypress);
_337        $inputText.on('keypress', handleInputTextKeypress);
_337        $newChannelInput.on('keypress', tc.handleNewChannelInputKeypress);
_337        $('#connect-image').on('click', connectClientWithUsername);
_337        $('#add-channel-image').on('click', showAddChannelInput);
_337        $('#leave-span').on('click', disconnectClient);
_337        $('#delete-channel-span').on('click', deleteCurrentChannel);
_337    });
_337
_337    function handleUsernameInputKeypress(event) {
_337        if (event.keyCode === 13) {
_337            connectClientWithUsername();
_337        }
_337    }
_337
_337    function handleInputTextKeypress(event) {
_337        if (event.keyCode === 13) {
_337            tc.currentChannel.sendMessage($(this).val());
_337            event.preventDefault();
_337            $(this).val('');
_337        }
_337        else {
_337            notifyTyping();
_337        }
_337    }
_337
_337    var notifyTyping = $.throttle(function () {
_337        tc.currentChannel.typing();
_337    }, 1000);
_337
_337    tc.handleNewChannelInputKeypress = function (event) {
_337        if (event.keyCode === 13) {
_337            tc.messagingClient.createChannel({
_337                friendlyName: $newChannelInput.val()
_337            }).then(hideAddChannelInput);
_337            $(this).val('');
_337            event.preventDefault();
_337        }
_337    };
_337
_337    function connectClientWithUsername() {
_337        var usernameText = $usernameInput.val();
_337        $usernameInput.val('');
_337        if (usernameText == '') {
_337            alert('Username cannot be empty');
_337            return;
_337        }
_337        tc.username = usernameText;
_337        fetchAccessToken(tc.username, connectMessagingClient);
_337    }
_337
_337    function fetchAccessToken(username, handler) {
_337        $.post('/token', {
_337            identity: username,
_337            device: 'browser'
_337        }, function (data) {
_337            handler(data);
_337        }, 'json');
_337    }
_337
_337    function connectMessagingClient(tokenResponse) {
_337        // Initialize the IP messaging client
_337        tc.accessManager = new Twilio.AccessManager(tokenResponse.token);
_337        tc.messagingClient = new Twilio.IPMessaging.Client(tc.accessManager);
_337        updateConnectedUI();
_337        tc.loadChannelList(tc.joinGeneralChannel);
_337        tc.messagingClient.on('channelAdded', $.throttle(tc.loadChannelList));
_337        tc.messagingClient.on('channelRemoved', $.throttle(tc.loadChannelList));
_337        tc.messagingClient.on('tokenExpired', refreshToken);
_337    }
_337
_337    function refreshToken() {
_337        fetchAccessToken(tc.username, setNewToken);
_337    }
_337
_337    function setNewToken(tokenResponse) {
_337        tc.accessManager.updateToken(tokenResponse.token);
_337    }
_337
_337    function updateConnectedUI() {
_337        $('#username-span').text(tc.username);
_337        $statusRow.addClass('connected').removeClass('disconnected');
_337        tc.$messageList.addClass('connected').removeClass('disconnected');
_337        $connectPanel.addClass('connected').removeClass('disconnected');
_337        $inputText.addClass('with-shadow');
_337        $typingRow.addClass('connected').removeClass('disconnected');
_337    }
_337
_337    tc.loadChannelList = function (handler) {
_337        if (tc.messagingClient === undefined) {
_337            console.log('Client is not initialized');
_337            return;
_337        }
_337
_337        tc.messagingClient.getChannels().then(function (channels) {
_337            tc.channelArray = tc.sortChannelsByName(channels);
_337            $channelList.text('');
_337            tc.channelArray.forEach(addChannel);
_337            if (typeof handler === 'function') {
_337                handler();
_337            }
_337        });
_337    };
_337
_337    tc.joinGeneralChannel = function () {
_337        console.log('Attempting to join "general" chat channel...');
_337        if (!tc.generalChannel) {
_337            // If it doesn't exist, let's create it
_337            tc.messagingClient.createChannel({
_337                uniqueName: GENERAL_CHANNEL_UNIQUE_NAME,
_337                friendlyName: GENERAL_CHANNEL_NAME
_337            }).then(function (channel) {
_337                console.log('Created general channel');
_337                tc.generalChannel = channel;
_337                tc.loadChannelList(tc.joinGeneralChannel);
_337            });
_337        }
_337        else {
_337            console.log('Found general channel:');
_337            setupChannel(tc.generalChannel);
_337        }
_337    };
_337
_337    function setupChannel(channel) {
_337        // Join the channel
_337        channel.join().then(function (joinedChannel) {
_337            console.log('Joined channel ' + joinedChannel.friendlyName);
_337            leaveCurrentChannel();
_337            updateChannelUI(channel);
_337            tc.currentChannel = channel;
_337            tc.loadMessages();
_337            channel.on('messageAdded', tc.addMessageToList);
_337            channel.on('typingStarted', showTypingStarted);
_337            channel.on('typingEnded', hideTypingStarted);
_337            channel.on('memberJoined', notifyMemberJoined);
_337            channel.on('memberLeft', notifyMemberLeft);
_337            $inputText.prop('disabled', false).focus();
_337            tc.$messageList.text('');
_337        });
_337    }
_337
_337    tc.loadMessages = function () {
_337        tc.currentChannel.getMessages(MESSAGES_HISTORY_LIMIT).then(function (messages) {
_337            messages.forEach(tc.addMessageToList);
_337        });
_337    };
_337
_337    function leaveCurrentChannel() {
_337        if (tc.currentChannel) {
_337            tc.currentChannel.leave().then(function (leftChannel) {
_337                console.log('left ' + leftChannel.friendlyName);
_337                leftChannel.removeListener('messageAdded', tc.addMessageToList);
_337                leftChannel.removeListener('typingStarted', showTypingStarted);
_337                leftChannel.removeListener('typingEnded', hideTypingStarted);
_337                leftChannel.removeListener('memberJoined', notifyMemberJoined);
_337                leftChannel.removeListener('memberLeft', notifyMemberLeft);
_337            });
_337        }
_337    }
_337
_337    tc.addMessageToList = function (message) {
_337        var rowDiv = $('<div>').addClass('row no-margin');
_337        rowDiv.loadTemplate($('#message-template'), {
_337            username: message.author,
_337            date: dateFormatter.getTodayDate(message.timestamp),
_337            body: message.body
_337        });
_337        if (message.author === tc.username) {
_337            rowDiv.addClass('own-message');
_337        }
_337
_337        tc.$messageList.append(rowDiv);
_337        scrollToMessageListBottom();
_337    };
_337
_337    function notifyMemberJoined(member) {
_337        notify(member.identity + ' joined the channel')
_337    }
_337
_337    function notifyMemberLeft(member) {
_337        notify(member.identity + ' left the channel');
_337    }
_337
_337    function notify(message) {
_337        var row = $('<div>').addClass('col-md-12');
_337        row.loadTemplate('#member-notification-template', {
_337            status: message
_337        });
_337        tc.$messageList.append(row);
_337        scrollToMessageListBottom();
_337    }
_337
_337    function showTypingStarted(member) {
_337        $typingPlaceholder.text(member.identity + ' is typing...');
_337    }
_337
_337    function hideTypingStarted(member) {
_337        $typingPlaceholder.text('');
_337    }
_337
_337    function scrollToMessageListBottom() {
_337        tc.$messageList.scrollTop(tc.$messageList[0].scrollHeight);
_337    }
_337
_337    function updateChannelUI(selectedChannel) {
_337        var channelElements = $('.channel-element').toArray();
_337        var channelElement = channelElements.filter(function (element) {
_337            return $(element).data().sid === selectedChannel.sid;
_337        });
_337        channelElement = $(channelElement);
_337        if (tc.currentChannelContainer === undefined && selectedChannel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_337            tc.currentChannelContainer = channelElement;
_337        }
_337        tc.currentChannelContainer.removeClass('selected-channel').addClass('unselected-channel');
_337        channelElement.removeClass('unselected-channel').addClass('selected-channel');
_337        tc.currentChannelContainer = channelElement;
_337    }
_337
_337    function showAddChannelInput() {
_337        if (tc.messagingClient) {
_337            $newChannelInputRow.addClass('showing').removeClass('not-showing');
_337            $channelList.addClass('showing').removeClass('not-showing');
_337            $newChannelInput.focus();
_337        }
_337    }
_337
_337    function hideAddChannelInput() {
_337        $newChannelInputRow.addClass('not-showing').removeClass('showing');
_337        $channelList.addClass('not-showing').removeClass('showing');
_337        $newChannelInput.val('');
_337    }
_337
_337    function addChannel(channel) {
_337        if (channel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_337            tc.generalChannel = channel;
_337        }
_337        var rowDiv = $('<div>').addClass('row channel-row');
_337        rowDiv.loadTemplate('#channel-template', {
_337            channelName: channel.friendlyName
_337        });
_337
_337        var channelP = rowDiv.children().children().first();
_337
_337        rowDiv.on('click', selectChannel);
_337        channelP.data('sid', channel.sid);
_337        if (tc.currentChannel && channel.sid === tc.currentChannel.sid) {
_337            tc.currentChannelContainer = channelP;
_337            channelP.addClass('selected-channel');
_337        }
_337        else {
_337            channelP.addClass('unselected-channel')
_337        }
_337
_337        $channelList.append(rowDiv);
_337    }
_337
_337    function deleteCurrentChannel() {
_337        if (!tc.currentChannel) {
_337            return;
_337        }
_337        if (tc.currentChannel.sid === tc.generalChannel.sid) {
_337            alert('You cannot delete the general channel');
_337            return;
_337        }
_337        tc.currentChannel.delete().then(function (channel) {
_337            console.log('channel: ' + channel.friendlyName + ' deleted');
_337            setupChannel(tc.generalChannel);
_337        });
_337    }
_337
_337    function selectChannel(event) {
_337        var target = $(event.target);
_337        var channelSid = target.data().sid;
_337        var selectedChannel = tc.channelArray.filter(function (channel) {
_337            return channel.sid === channelSid;
_337        })[0];
_337        if (selectedChannel === tc.currentChannel) {
_337            return;
_337        }
_337        setupChannel(selectedChannel);
_337    };
_337
_337    function disconnectClient() {
_337        leaveCurrentChannel();
_337        $channelList.text('');
_337        tc.$messageList.text('');
_337        channels = undefined;
_337        $statusRow.addClass('disconnected').removeClass('connected');
_337        tc.$messageList.addClass('disconnected').removeClass('connected');
_337        $connectPanel.addClass('disconnected').removeClass('connected');
_337        $inputText.removeClass('with-shadow');
_337        $typingRow.addClass('disconnected').removeClass('connected');
_337    }
_337
_337    tc.sortChannelsByName = function (channels) {
_337        return channels.sort(function (a, b) {
_337            if (a.friendlyName === GENERAL_CHANNEL_NAME) {
_337                return -1;
_337            }
_337            if (b.friendlyName === GENERAL_CHANNEL_NAME) {
_337                return 1;
_337            }
_337            return a.friendlyName.localeCompare(b.friendlyName);
_337        });
_337    };
_337
_337    return tc;
_337})();

Now let's listen for some channel events.

Listen to Channel Events

With access to the channel objects we can use them to listen to a series of events. In our case, we're setting listeners to the following events:

messageAdded : When another member sends a message to the channel you are connected to.
typingStarted : When another member is typing a message on the channel that you are connected to.
typingEnded : When another member stops typing a message on the channel that you are connected to.
memberJoined : When another member joins the channel that you are connected to.
memberLeft : When another member leaves the channel that you are connected to.

Here, we just register a different function to handle each particular event.

Listen to Channel Events

TwilioChat.Web/Scripts/twiliochat.js


_337var twiliochat = (function () {
_337    var tc = {};
_337
_337    var GENERAL_CHANNEL_UNIQUE_NAME = 'general';
_337    var GENERAL_CHANNEL_NAME = 'General Channel';
_337    var MESSAGES_HISTORY_LIMIT = 50;
_337
_337    var $channelList;
_337    var $inputText;
_337    var $usernameInput;
_337    var $statusRow;
_337    var $connectPanel;
_337    var $newChannelInputRow;
_337    var $newChannelInput;
_337    var $typingRow;
_337    var $typingPlaceholder;
_337
_337    $(document).ready(function () {
_337        tc.$messageList = $('#message-list');
_337        $channelList = $('#channel-list');
_337        $inputText = $('#input-text');
_337        $usernameInput = $('#username-input');
_337        $statusRow = $('#status-row');
_337        $connectPanel = $('#connect-panel');
_337        $newChannelInputRow = $('#new-channel-input-row');
_337        $newChannelInput = $('#new-channel-input');
_337        $typingRow = $('#typing-row');
_337        $typingPlaceholder = $('#typing-placeholder');
_337        $usernameInput.focus();
_337        $usernameInput.on('keypress', handleUsernameInputKeypress);
_337        $inputText.on('keypress', handleInputTextKeypress);
_337        $newChannelInput.on('keypress', tc.handleNewChannelInputKeypress);
_337        $('#connect-image').on('click', connectClientWithUsername);
_337        $('#add-channel-image').on('click', showAddChannelInput);
_337        $('#leave-span').on('click', disconnectClient);
_337        $('#delete-channel-span').on('click', deleteCurrentChannel);
_337    });
_337
_337    function handleUsernameInputKeypress(event) {
_337        if (event.keyCode === 13) {
_337            connectClientWithUsername();
_337        }
_337    }
_337
_337    function handleInputTextKeypress(event) {
_337        if (event.keyCode === 13) {
_337            tc.currentChannel.sendMessage($(this).val());
_337            event.preventDefault();
_337            $(this).val('');
_337        }
_337        else {
_337            notifyTyping();
_337        }
_337    }
_337
_337    var notifyTyping = $.throttle(function () {
_337        tc.currentChannel.typing();
_337    }, 1000);
_337
_337    tc.handleNewChannelInputKeypress = function (event) {
_337        if (event.keyCode === 13) {
_337            tc.messagingClient.createChannel({
_337                friendlyName: $newChannelInput.val()
_337            }).then(hideAddChannelInput);
_337            $(this).val('');
_337            event.preventDefault();
_337        }
_337    };
_337
_337    function connectClientWithUsername() {
_337        var usernameText = $usernameInput.val();
_337        $usernameInput.val('');
_337        if (usernameText == '') {
_337            alert('Username cannot be empty');
_337            return;
_337        }
_337        tc.username = usernameText;
_337        fetchAccessToken(tc.username, connectMessagingClient);
_337    }
_337
_337    function fetchAccessToken(username, handler) {
_337        $.post('/token', {
_337            identity: username,
_337            device: 'browser'
_337        }, function (data) {
_337            handler(data);
_337        }, 'json');
_337    }
_337
_337    function connectMessagingClient(tokenResponse) {
_337        // Initialize the IP messaging client
_337        tc.accessManager = new Twilio.AccessManager(tokenResponse.token);
_337        tc.messagingClient = new Twilio.IPMessaging.Client(tc.accessManager);
_337        updateConnectedUI();
_337        tc.loadChannelList(tc.joinGeneralChannel);
_337        tc.messagingClient.on('channelAdded', $.throttle(tc.loadChannelList));
_337        tc.messagingClient.on('channelRemoved', $.throttle(tc.loadChannelList));
_337        tc.messagingClient.on('tokenExpired', refreshToken);
_337    }
_337
_337    function refreshToken() {
_337        fetchAccessToken(tc.username, setNewToken);
_337    }
_337
_337    function setNewToken(tokenResponse) {
_337        tc.accessManager.updateToken(tokenResponse.token);
_337    }
_337
_337    function updateConnectedUI() {
_337        $('#username-span').text(tc.username);
_337        $statusRow.addClass('connected').removeClass('disconnected');
_337        tc.$messageList.addClass('connected').removeClass('disconnected');
_337        $connectPanel.addClass('connected').removeClass('disconnected');
_337        $inputText.addClass('with-shadow');
_337        $typingRow.addClass('connected').removeClass('disconnected');
_337    }
_337
_337    tc.loadChannelList = function (handler) {
_337        if (tc.messagingClient === undefined) {
_337            console.log('Client is not initialized');
_337            return;
_337        }
_337
_337        tc.messagingClient.getChannels().then(function (channels) {
_337            tc.channelArray = tc.sortChannelsByName(channels);
_337            $channelList.text('');
_337            tc.channelArray.forEach(addChannel);
_337            if (typeof handler === 'function') {
_337                handler();
_337            }
_337        });
_337    };
_337
_337    tc.joinGeneralChannel = function () {
_337        console.log('Attempting to join "general" chat channel...');
_337        if (!tc.generalChannel) {
_337            // If it doesn't exist, let's create it
_337            tc.messagingClient.createChannel({
_337                uniqueName: GENERAL_CHANNEL_UNIQUE_NAME,
_337                friendlyName: GENERAL_CHANNEL_NAME
_337            }).then(function (channel) {
_337                console.log('Created general channel');
_337                tc.generalChannel = channel;
_337                tc.loadChannelList(tc.joinGeneralChannel);
_337            });
_337        }
_337        else {
_337            console.log('Found general channel:');
_337            setupChannel(tc.generalChannel);
_337        }
_337    };
_337
_337    function setupChannel(channel) {
_337        // Join the channel
_337        channel.join().then(function (joinedChannel) {
_337            console.log('Joined channel ' + joinedChannel.friendlyName);
_337            leaveCurrentChannel();
_337            updateChannelUI(channel);
_337            tc.currentChannel = channel;
_337            tc.loadMessages();
_337            channel.on('messageAdded', tc.addMessageToList);
_337            channel.on('typingStarted', showTypingStarted);
_337            channel.on('typingEnded', hideTypingStarted);
_337            channel.on('memberJoined', notifyMemberJoined);
_337            channel.on('memberLeft', notifyMemberLeft);
_337            $inputText.prop('disabled', false).focus();
_337            tc.$messageList.text('');
_337        });
_337    }
_337
_337    tc.loadMessages = function () {
_337        tc.currentChannel.getMessages(MESSAGES_HISTORY_LIMIT).then(function (messages) {
_337            messages.forEach(tc.addMessageToList);
_337        });
_337    };
_337
_337    function leaveCurrentChannel() {
_337        if (tc.currentChannel) {
_337            tc.currentChannel.leave().then(function (leftChannel) {
_337                console.log('left ' + leftChannel.friendlyName);
_337                leftChannel.removeListener('messageAdded', tc.addMessageToList);
_337                leftChannel.removeListener('typingStarted', showTypingStarted);
_337                leftChannel.removeListener('typingEnded', hideTypingStarted);
_337                leftChannel.removeListener('memberJoined', notifyMemberJoined);
_337                leftChannel.removeListener('memberLeft', notifyMemberLeft);
_337            });
_337        }
_337    }
_337
_337    tc.addMessageToList = function (message) {
_337        var rowDiv = $('<div>').addClass('row no-margin');
_337        rowDiv.loadTemplate($('#message-template'), {
_337            username: message.author,
_337            date: dateFormatter.getTodayDate(message.timestamp),
_337            body: message.body
_337        });
_337        if (message.author === tc.username) {
_337            rowDiv.addClass('own-message');
_337        }
_337
_337        tc.$messageList.append(rowDiv);
_337        scrollToMessageListBottom();
_337    };
_337
_337    function notifyMemberJoined(member) {
_337        notify(member.identity + ' joined the channel')
_337    }
_337
_337    function notifyMemberLeft(member) {
_337        notify(member.identity + ' left the channel');
_337    }
_337
_337    function notify(message) {
_337        var row = $('<div>').addClass('col-md-12');
_337        row.loadTemplate('#member-notification-template', {
_337            status: message
_337        });
_337        tc.$messageList.append(row);
_337        scrollToMessageListBottom();
_337    }
_337
_337    function showTypingStarted(member) {
_337        $typingPlaceholder.text(member.identity + ' is typing...');
_337    }
_337
_337    function hideTypingStarted(member) {
_337        $typingPlaceholder.text('');
_337    }
_337
_337    function scrollToMessageListBottom() {
_337        tc.$messageList.scrollTop(tc.$messageList[0].scrollHeight);
_337    }
_337
_337    function updateChannelUI(selectedChannel) {
_337        var channelElements = $('.channel-element').toArray();
_337        var channelElement = channelElements.filter(function (element) {
_337            return $(element).data().sid === selectedChannel.sid;
_337        });
_337        channelElement = $(channelElement);
_337        if (tc.currentChannelContainer === undefined && selectedChannel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_337            tc.currentChannelContainer = channelElement;
_337        }
_337        tc.currentChannelContainer.removeClass('selected-channel').addClass('unselected-channel');
_337        channelElement.removeClass('unselected-channel').addClass('selected-channel');
_337        tc.currentChannelContainer = channelElement;
_337    }
_337
_337    function showAddChannelInput() {
_337        if (tc.messagingClient) {
_337            $newChannelInputRow.addClass('showing').removeClass('not-showing');
_337            $channelList.addClass('showing').removeClass('not-showing');
_337            $newChannelInput.focus();
_337        }
_337    }
_337
_337    function hideAddChannelInput() {
_337        $newChannelInputRow.addClass('not-showing').removeClass('showing');
_337        $channelList.addClass('not-showing').removeClass('showing');
_337        $newChannelInput.val('');
_337    }
_337
_337    function addChannel(channel) {
_337        if (channel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_337            tc.generalChannel = channel;
_337        }
_337        var rowDiv = $('<div>').addClass('row channel-row');
_337        rowDiv.loadTemplate('#channel-template', {
_337            channelName: channel.friendlyName
_337        });
_337
_337        var channelP = rowDiv.children().children().first();
_337
_337        rowDiv.on('click', selectChannel);
_337        channelP.data('sid', channel.sid);
_337        if (tc.currentChannel && channel.sid === tc.currentChannel.sid) {
_337            tc.currentChannelContainer = channelP;
_337            channelP.addClass('selected-channel');
_337        }
_337        else {
_337            channelP.addClass('unselected-channel')
_337        }
_337
_337        $channelList.append(rowDiv);
_337    }
_337
_337    function deleteCurrentChannel() {
_337        if (!tc.currentChannel) {
_337            return;
_337        }
_337        if (tc.currentChannel.sid === tc.generalChannel.sid) {
_337            alert('You cannot delete the general channel');
_337            return;
_337        }
_337        tc.currentChannel.delete().then(function (channel) {
_337            console.log('channel: ' + channel.friendlyName + ' deleted');
_337            setupChannel(tc.generalChannel);
_337        });
_337    }
_337
_337    function selectChannel(event) {
_337        var target = $(event.target);
_337        var channelSid = target.data().sid;
_337        var selectedChannel = tc.channelArray.filter(function (channel) {
_337            return channel.sid === channelSid;
_337        })[0];
_337        if (selectedChannel === tc.currentChannel) {
_337            return;
_337        }
_337        setupChannel(selectedChannel);
_337    };
_337
_337    function disconnectClient() {
_337        leaveCurrentChannel();
_337        $channelList.text('');
_337        tc.$messageList.text('');
_337        channels = undefined;
_337        $statusRow.addClass('disconnected').removeClass('connected');
_337        tc.$messageList.addClass('disconnected').removeClass('connected');
_337        $connectPanel.addClass('disconnected').removeClass('connected');
_337        $inputText.removeClass('with-shadow');
_337        $typingRow.addClass('disconnected').removeClass('connected');
_337    }
_337
_337    tc.sortChannelsByName = function (channels) {
_337        return channels.sort(function (a, b) {
_337            if (a.friendlyName === GENERAL_CHANNEL_NAME) {
_337                return -1;
_337            }
_337            if (b.friendlyName === GENERAL_CHANNEL_NAME) {
_337                return 1;
_337            }
_337            return a.friendlyName.localeCompare(b.friendlyName);
_337        });
_337    };
_337
_337    return tc;
_337})();

The client emits events as well. Let's see how we can listen to those events as well.

Listen to Client Events

Just like with channels, we can register handlers for events on the Client:

channelAdded : When a channel becomes visible to the Client.
channelRemoved : When a channel is no longer visible to the Client.
tokenExpired : When the supplied token expires.

Listen to Client Events

TwilioChat.Web/Scripts/twiliochat.js


_337var twiliochat = (function () {
_337    var tc = {};
_337
_337    var GENERAL_CHANNEL_UNIQUE_NAME = 'general';
_337    var GENERAL_CHANNEL_NAME = 'General Channel';
_337    var MESSAGES_HISTORY_LIMIT = 50;
_337
_337    var $channelList;
_337    var $inputText;
_337    var $usernameInput;
_337    var $statusRow;
_337    var $connectPanel;
_337    var $newChannelInputRow;
_337    var $newChannelInput;
_337    var $typingRow;
_337    var $typingPlaceholder;
_337
_337    $(document).ready(function () {
_337        tc.$messageList = $('#message-list');
_337        $channelList = $('#channel-list');
_337        $inputText = $('#input-text');
_337        $usernameInput = $('#username-input');
_337        $statusRow = $('#status-row');
_337        $connectPanel = $('#connect-panel');
_337        $newChannelInputRow = $('#new-channel-input-row');
_337        $newChannelInput = $('#new-channel-input');
_337        $typingRow = $('#typing-row');
_337        $typingPlaceholder = $('#typing-placeholder');
_337        $usernameInput.focus();
_337        $usernameInput.on('keypress', handleUsernameInputKeypress);
_337        $inputText.on('keypress', handleInputTextKeypress);
_337        $newChannelInput.on('keypress', tc.handleNewChannelInputKeypress);
_337        $('#connect-image').on('click', connectClientWithUsername);
_337        $('#add-channel-image').on('click', showAddChannelInput);
_337        $('#leave-span').on('click', disconnectClient);
_337        $('#delete-channel-span').on('click', deleteCurrentChannel);
_337    });
_337
_337    function handleUsernameInputKeypress(event) {
_337        if (event.keyCode === 13) {
_337            connectClientWithUsername();
_337        }
_337    }
_337
_337    function handleInputTextKeypress(event) {
_337        if (event.keyCode === 13) {
_337            tc.currentChannel.sendMessage($(this).val());
_337            event.preventDefault();
_337            $(this).val('');
_337        }
_337        else {
_337            notifyTyping();
_337        }
_337    }
_337
_337    var notifyTyping = $.throttle(function () {
_337        tc.currentChannel.typing();
_337    }, 1000);
_337
_337    tc.handleNewChannelInputKeypress = function (event) {
_337        if (event.keyCode === 13) {
_337            tc.messagingClient.createChannel({
_337                friendlyName: $newChannelInput.val()
_337            }).then(hideAddChannelInput);
_337            $(this).val('');
_337            event.preventDefault();
_337        }
_337    };
_337
_337    function connectClientWithUsername() {
_337        var usernameText = $usernameInput.val();
_337        $usernameInput.val('');
_337        if (usernameText == '') {
_337            alert('Username cannot be empty');
_337            return;
_337        }
_337        tc.username = usernameText;
_337        fetchAccessToken(tc.username, connectMessagingClient);
_337    }
_337
_337    function fetchAccessToken(username, handler) {
_337        $.post('/token', {
_337            identity: username,
_337            device: 'browser'
_337        }, function (data) {
_337            handler(data);
_337        }, 'json');
_337    }
_337
_337    function connectMessagingClient(tokenResponse) {
_337        // Initialize the IP messaging client
_337        tc.accessManager = new Twilio.AccessManager(tokenResponse.token);
_337        tc.messagingClient = new Twilio.IPMessaging.Client(tc.accessManager);
_337        updateConnectedUI();
_337        tc.loadChannelList(tc.joinGeneralChannel);
_337        tc.messagingClient.on('channelAdded', $.throttle(tc.loadChannelList));
_337        tc.messagingClient.on('channelRemoved', $.throttle(tc.loadChannelList));
_337        tc.messagingClient.on('tokenExpired', refreshToken);
_337    }
_337
_337    function refreshToken() {
_337        fetchAccessToken(tc.username, setNewToken);
_337    }
_337
_337    function setNewToken(tokenResponse) {
_337        tc.accessManager.updateToken(tokenResponse.token);
_337    }
_337
_337    function updateConnectedUI() {
_337        $('#username-span').text(tc.username);
_337        $statusRow.addClass('connected').removeClass('disconnected');
_337        tc.$messageList.addClass('connected').removeClass('disconnected');
_337        $connectPanel.addClass('connected').removeClass('disconnected');
_337        $inputText.addClass('with-shadow');
_337        $typingRow.addClass('connected').removeClass('disconnected');
_337    }
_337
_337    tc.loadChannelList = function (handler) {
_337        if (tc.messagingClient === undefined) {
_337            console.log('Client is not initialized');
_337            return;
_337        }
_337
_337        tc.messagingClient.getChannels().then(function (channels) {
_337            tc.channelArray = tc.sortChannelsByName(channels);
_337            $channelList.text('');
_337            tc.channelArray.forEach(addChannel);
_337            if (typeof handler === 'function') {
_337                handler();
_337            }
_337        });
_337    };
_337
_337    tc.joinGeneralChannel = function () {
_337        console.log('Attempting to join "general" chat channel...');
_337        if (!tc.generalChannel) {
_337            // If it doesn't exist, let's create it
_337            tc.messagingClient.createChannel({
_337                uniqueName: GENERAL_CHANNEL_UNIQUE_NAME,
_337                friendlyName: GENERAL_CHANNEL_NAME
_337            }).then(function (channel) {
_337                console.log('Created general channel');
_337                tc.generalChannel = channel;
_337                tc.loadChannelList(tc.joinGeneralChannel);
_337            });
_337        }
_337        else {
_337            console.log('Found general channel:');
_337            setupChannel(tc.generalChannel);
_337        }
_337    };
_337
_337    function setupChannel(channel) {
_337        // Join the channel
_337        channel.join().then(function (joinedChannel) {
_337            console.log('Joined channel ' + joinedChannel.friendlyName);
_337            leaveCurrentChannel();
_337            updateChannelUI(channel);
_337            tc.currentChannel = channel;
_337            tc.loadMessages();
_337            channel.on('messageAdded', tc.addMessageToList);
_337            channel.on('typingStarted', showTypingStarted);
_337            channel.on('typingEnded', hideTypingStarted);
_337            channel.on('memberJoined', notifyMemberJoined);
_337            channel.on('memberLeft', notifyMemberLeft);
_337            $inputText.prop('disabled', false).focus();
_337            tc.$messageList.text('');
_337        });
_337    }
_337
_337    tc.loadMessages = function () {
_337        tc.currentChannel.getMessages(MESSAGES_HISTORY_LIMIT).then(function (messages) {
_337            messages.forEach(tc.addMessageToList);
_337        });
_337    };
_337
_337    function leaveCurrentChannel() {
_337        if (tc.currentChannel) {
_337            tc.currentChannel.leave().then(function (leftChannel) {
_337                console.log('left ' + leftChannel.friendlyName);
_337                leftChannel.removeListener('messageAdded', tc.addMessageToList);
_337                leftChannel.removeListener('typingStarted', showTypingStarted);
_337                leftChannel.removeListener('typingEnded', hideTypingStarted);
_337                leftChannel.removeListener('memberJoined', notifyMemberJoined);
_337                leftChannel.removeListener('memberLeft', notifyMemberLeft);
_337            });
_337        }
_337    }
_337
_337    tc.addMessageToList = function (message) {
_337        var rowDiv = $('<div>').addClass('row no-margin');
_337        rowDiv.loadTemplate($('#message-template'), {
_337            username: message.author,
_337            date: dateFormatter.getTodayDate(message.timestamp),
_337            body: message.body
_337        });
_337        if (message.author === tc.username) {
_337            rowDiv.addClass('own-message');
_337        }
_337
_337        tc.$messageList.append(rowDiv);
_337        scrollToMessageListBottom();
_337    };
_337
_337    function notifyMemberJoined(member) {
_337        notify(member.identity + ' joined the channel')
_337    }
_337
_337    function notifyMemberLeft(member) {
_337        notify(member.identity + ' left the channel');
_337    }
_337
_337    function notify(message) {
_337        var row = $('<div>').addClass('col-md-12');
_337        row.loadTemplate('#member-notification-template', {
_337            status: message
_337        });
_337        tc.$messageList.append(row);
_337        scrollToMessageListBottom();
_337    }
_337
_337    function showTypingStarted(member) {
_337        $typingPlaceholder.text(member.identity + ' is typing...');
_337    }
_337
_337    function hideTypingStarted(member) {
_337        $typingPlaceholder.text('');
_337    }
_337
_337    function scrollToMessageListBottom() {
_337        tc.$messageList.scrollTop(tc.$messageList[0].scrollHeight);
_337    }
_337
_337    function updateChannelUI(selectedChannel) {
_337        var channelElements = $('.channel-element').toArray();
_337        var channelElement = channelElements.filter(function (element) {
_337            return $(element).data().sid === selectedChannel.sid;
_337        });
_337        channelElement = $(channelElement);
_337        if (tc.currentChannelContainer === undefined && selectedChannel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_337            tc.currentChannelContainer = channelElement;
_337        }
_337        tc.currentChannelContainer.removeClass('selected-channel').addClass('unselected-channel');
_337        channelElement.removeClass('unselected-channel').addClass('selected-channel');
_337        tc.currentChannelContainer = channelElement;
_337    }
_337
_337    function showAddChannelInput() {
_337        if (tc.messagingClient) {
_337            $newChannelInputRow.addClass('showing').removeClass('not-showing');
_337            $channelList.addClass('showing').removeClass('not-showing');
_337            $newChannelInput.focus();
_337        }
_337    }
_337
_337    function hideAddChannelInput() {
_337        $newChannelInputRow.addClass('not-showing').removeClass('showing');
_337        $channelList.addClass('not-showing').removeClass('showing');
_337        $newChannelInput.val('');
_337    }
_337
_337    function addChannel(channel) {
_337        if (channel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_337            tc.generalChannel = channel;
_337        }
_337        var rowDiv = $('<div>').addClass('row channel-row');
_337        rowDiv.loadTemplate('#channel-template', {
_337            channelName: channel.friendlyName
_337        });
_337
_337        var channelP = rowDiv.children().children().first();
_337
_337        rowDiv.on('click', selectChannel);
_337        channelP.data('sid', channel.sid);
_337        if (tc.currentChannel && channel.sid === tc.currentChannel.sid) {
_337            tc.currentChannelContainer = channelP;
_337            channelP.addClass('selected-channel');
_337        }
_337        else {
_337            channelP.addClass('unselected-channel')
_337        }
_337
_337        $channelList.append(rowDiv);
_337    }
_337
_337    function deleteCurrentChannel() {
_337        if (!tc.currentChannel) {
_337            return;
_337        }
_337        if (tc.currentChannel.sid === tc.generalChannel.sid) {
_337            alert('You cannot delete the general channel');
_337            return;
_337        }
_337        tc.currentChannel.delete().then(function (channel) {
_337            console.log('channel: ' + channel.friendlyName + ' deleted');
_337            setupChannel(tc.generalChannel);
_337        });
_337    }
_337
_337    function selectChannel(event) {
_337        var target = $(event.target);
_337        var channelSid = target.data().sid;
_337        var selectedChannel = tc.channelArray.filter(function (channel) {
_337            return channel.sid === channelSid;
_337        })[0];
_337        if (selectedChannel === tc.currentChannel) {
_337            return;
_337        }
_337        setupChannel(selectedChannel);
_337    };
_337
_337    function disconnectClient() {
_337        leaveCurrentChannel();
_337        $channelList.text('');
_337        tc.$messageList.text('');
_337        channels = undefined;
_337        $statusRow.addClass('disconnected').removeClass('connected');
_337        tc.$messageList.addClass('disconnected').removeClass('connected');
_337        $connectPanel.addClass('disconnected').removeClass('connected');
_337        $inputText.removeClass('with-shadow');
_337        $typingRow.addClass('disconnected').removeClass('connected');
_337    }
_337
_337    tc.sortChannelsByName = function (channels) {
_337        return channels.sort(function (a, b) {
_337            if (a.friendlyName === GENERAL_CHANNEL_NAME) {
_337                return -1;
_337            }
_337            if (b.friendlyName === GENERAL_CHANNEL_NAME) {
_337                return 1;
_337            }
_337            return a.friendlyName.localeCompare(b.friendlyName);
_337        });
_337    };
_337
_337    return tc;
_337})();

We've actually got a real chat app going here, but let's make it more interesting with multiple channels.

Create a Channel

To create a new channel, the user clicks on the "+ Channel" link. That we'll show an input text field where it's possible to type the name of the new channel. The only restriction here, is that the user can't create a channel called "General Channel". Other than that, creating a channel is as simple as calling createChannel with an object that has the friendlyName key. You can create a channel with more options though, see a list of the options here.

Create a Channel

TwilioChat.Web/Scripts/twiliochat.js


_337var twiliochat = (function () {
_337    var tc = {};
_337
_337    var GENERAL_CHANNEL_UNIQUE_NAME = 'general';
_337    var GENERAL_CHANNEL_NAME = 'General Channel';
_337    var MESSAGES_HISTORY_LIMIT = 50;
_337
_337    var $channelList;
_337    var $inputText;
_337    var $usernameInput;
_337    var $statusRow;
_337    var $connectPanel;
_337    var $newChannelInputRow;
_337    var $newChannelInput;
_337    var $typingRow;
_337    var $typingPlaceholder;
_337
_337    $(document).ready(function () {
_337        tc.$messageList = $('#message-list');
_337        $channelList = $('#channel-list');
_337        $inputText = $('#input-text');
_337        $usernameInput = $('#username-input');
_337        $statusRow = $('#status-row');
_337        $connectPanel = $('#connect-panel');
_337        $newChannelInputRow = $('#new-channel-input-row');
_337        $newChannelInput = $('#new-channel-input');
_337        $typingRow = $('#typing-row');
_337        $typingPlaceholder = $('#typing-placeholder');
_337        $usernameInput.focus();
_337        $usernameInput.on('keypress', handleUsernameInputKeypress);
_337        $inputText.on('keypress', handleInputTextKeypress);
_337        $newChannelInput.on('keypress', tc.handleNewChannelInputKeypress);
_337        $('#connect-image').on('click', connectClientWithUsername);
_337        $('#add-channel-image').on('click', showAddChannelInput);
_337        $('#leave-span').on('click', disconnectClient);
_337        $('#delete-channel-span').on('click', deleteCurrentChannel);
_337    });
_337
_337    function handleUsernameInputKeypress(event) {
_337        if (event.keyCode === 13) {
_337            connectClientWithUsername();
_337        }
_337    }
_337
_337    function handleInputTextKeypress(event) {
_337        if (event.keyCode === 13) {
_337            tc.currentChannel.sendMessage($(this).val());
_337            event.preventDefault();
_337            $(this).val('');
_337        }
_337        else {
_337            notifyTyping();
_337        }
_337    }
_337
_337    var notifyTyping = $.throttle(function () {
_337        tc.currentChannel.typing();
_337    }, 1000);
_337
_337    tc.handleNewChannelInputKeypress = function (event) {
_337        if (event.keyCode === 13) {
_337            tc.messagingClient.createChannel({
_337                friendlyName: $newChannelInput.val()
_337            }).then(hideAddChannelInput);
_337            $(this).val('');
_337            event.preventDefault();
_337        }
_337    };
_337
_337    function connectClientWithUsername() {
_337        var usernameText = $usernameInput.val();
_337        $usernameInput.val('');
_337        if (usernameText == '') {
_337            alert('Username cannot be empty');
_337            return;
_337        }
_337        tc.username = usernameText;
_337        fetchAccessToken(tc.username, connectMessagingClient);
_337    }
_337
_337    function fetchAccessToken(username, handler) {
_337        $.post('/token', {
_337            identity: username,
_337            device: 'browser'
_337        }, function (data) {
_337            handler(data);
_337        }, 'json');
_337    }
_337
_337    function connectMessagingClient(tokenResponse) {
_337        // Initialize the IP messaging client
_337        tc.accessManager = new Twilio.AccessManager(tokenResponse.token);
_337        tc.messagingClient = new Twilio.IPMessaging.Client(tc.accessManager);
_337        updateConnectedUI();
_337        tc.loadChannelList(tc.joinGeneralChannel);
_337        tc.messagingClient.on('channelAdded', $.throttle(tc.loadChannelList));
_337        tc.messagingClient.on('channelRemoved', $.throttle(tc.loadChannelList));
_337        tc.messagingClient.on('tokenExpired', refreshToken);
_337    }
_337
_337    function refreshToken() {
_337        fetchAccessToken(tc.username, setNewToken);
_337    }
_337
_337    function setNewToken(tokenResponse) {
_337        tc.accessManager.updateToken(tokenResponse.token);
_337    }
_337
_337    function updateConnectedUI() {
_337        $('#username-span').text(tc.username);
_337        $statusRow.addClass('connected').removeClass('disconnected');
_337        tc.$messageList.addClass('connected').removeClass('disconnected');
_337        $connectPanel.addClass('connected').removeClass('disconnected');
_337        $inputText.addClass('with-shadow');
_337        $typingRow.addClass('connected').removeClass('disconnected');
_337    }
_337
_337    tc.loadChannelList = function (handler) {
_337        if (tc.messagingClient === undefined) {
_337            console.log('Client is not initialized');
_337            return;
_337        }
_337
_337        tc.messagingClient.getChannels().then(function (channels) {
_337            tc.channelArray = tc.sortChannelsByName(channels);
_337            $channelList.text('');
_337            tc.channelArray.forEach(addChannel);
_337            if (typeof handler === 'function') {
_337                handler();
_337            }
_337        });
_337    };
_337
_337    tc.joinGeneralChannel = function () {
_337        console.log('Attempting to join "general" chat channel...');
_337        if (!tc.generalChannel) {
_337            // If it doesn't exist, let's create it
_337            tc.messagingClient.createChannel({
_337                uniqueName: GENERAL_CHANNEL_UNIQUE_NAME,
_337                friendlyName: GENERAL_CHANNEL_NAME
_337            }).then(function (channel) {
_337                console.log('Created general channel');
_337                tc.generalChannel = channel;
_337                tc.loadChannelList(tc.joinGeneralChannel);
_337            });
_337        }
_337        else {
_337            console.log('Found general channel:');
_337            setupChannel(tc.generalChannel);
_337        }
_337    };
_337
_337    function setupChannel(channel) {
_337        // Join the channel
_337        channel.join().then(function (joinedChannel) {
_337            console.log('Joined channel ' + joinedChannel.friendlyName);
_337            leaveCurrentChannel();
_337            updateChannelUI(channel);
_337            tc.currentChannel = channel;
_337            tc.loadMessages();
_337            channel.on('messageAdded', tc.addMessageToList);
_337            channel.on('typingStarted', showTypingStarted);
_337            channel.on('typingEnded', hideTypingStarted);
_337            channel.on('memberJoined', notifyMemberJoined);
_337            channel.on('memberLeft', notifyMemberLeft);
_337            $inputText.prop('disabled', false).focus();
_337            tc.$messageList.text('');
_337        });
_337    }
_337
_337    tc.loadMessages = function () {
_337        tc.currentChannel.getMessages(MESSAGES_HISTORY_LIMIT).then(function (messages) {
_337            messages.forEach(tc.addMessageToList);
_337        });
_337    };
_337
_337    function leaveCurrentChannel() {
_337        if (tc.currentChannel) {
_337            tc.currentChannel.leave().then(function (leftChannel) {
_337                console.log('left ' + leftChannel.friendlyName);
_337                leftChannel.removeListener('messageAdded', tc.addMessageToList);
_337                leftChannel.removeListener('typingStarted', showTypingStarted);
_337                leftChannel.removeListener('typingEnded', hideTypingStarted);
_337                leftChannel.removeListener('memberJoined', notifyMemberJoined);
_337                leftChannel.removeListener('memberLeft', notifyMemberLeft);
_337            });
_337        }
_337    }
_337
_337    tc.addMessageToList = function (message) {
_337        var rowDiv = $('<div>').addClass('row no-margin');
_337        rowDiv.loadTemplate($('#message-template'), {
_337            username: message.author,
_337            date: dateFormatter.getTodayDate(message.timestamp),
_337            body: message.body
_337        });
_337        if (message.author === tc.username) {
_337            rowDiv.addClass('own-message');
_337        }
_337
_337        tc.$messageList.append(rowDiv);
_337        scrollToMessageListBottom();
_337    };
_337
_337    function notifyMemberJoined(member) {
_337        notify(member.identity + ' joined the channel')
_337    }
_337
_337    function notifyMemberLeft(member) {
_337        notify(member.identity + ' left the channel');
_337    }
_337
_337    function notify(message) {
_337        var row = $('<div>').addClass('col-md-12');
_337        row.loadTemplate('#member-notification-template', {
_337            status: message
_337        });
_337        tc.$messageList.append(row);
_337        scrollToMessageListBottom();
_337    }
_337
_337    function showTypingStarted(member) {
_337        $typingPlaceholder.text(member.identity + ' is typing...');
_337    }
_337
_337    function hideTypingStarted(member) {
_337        $typingPlaceholder.text('');
_337    }
_337
_337    function scrollToMessageListBottom() {
_337        tc.$messageList.scrollTop(tc.$messageList[0].scrollHeight);
_337    }
_337
_337    function updateChannelUI(selectedChannel) {
_337        var channelElements = $('.channel-element').toArray();
_337        var channelElement = channelElements.filter(function (element) {
_337            return $(element).data().sid === selectedChannel.sid;
_337        });
_337        channelElement = $(channelElement);
_337        if (tc.currentChannelContainer === undefined && selectedChannel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_337            tc.currentChannelContainer = channelElement;
_337        }
_337        tc.currentChannelContainer.removeClass('selected-channel').addClass('unselected-channel');
_337        channelElement.removeClass('unselected-channel').addClass('selected-channel');
_337        tc.currentChannelContainer = channelElement;
_337    }
_337
_337    function showAddChannelInput() {
_337        if (tc.messagingClient) {
_337            $newChannelInputRow.addClass('showing').removeClass('not-showing');
_337            $channelList.addClass('showing').removeClass('not-showing');
_337            $newChannelInput.focus();
_337        }
_337    }
_337
_337    function hideAddChannelInput() {
_337        $newChannelInputRow.addClass('not-showing').removeClass('showing');
_337        $channelList.addClass('not-showing').removeClass('showing');
_337        $newChannelInput.val('');
_337    }
_337
_337    function addChannel(channel) {
_337        if (channel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_337            tc.generalChannel = channel;
_337        }
_337        var rowDiv = $('<div>').addClass('row channel-row');
_337        rowDiv.loadTemplate('#channel-template', {
_337            channelName: channel.friendlyName
_337        });
_337
_337        var channelP = rowDiv.children().children().first();
_337
_337        rowDiv.on('click', selectChannel);
_337        channelP.data('sid', channel.sid);
_337        if (tc.currentChannel && channel.sid === tc.currentChannel.sid) {
_337            tc.currentChannelContainer = channelP;
_337            channelP.addClass('selected-channel');
_337        }
_337        else {
_337            channelP.addClass('unselected-channel')
_337        }
_337
_337        $channelList.append(rowDiv);
_337    }
_337
_337    function deleteCurrentChannel() {
_337        if (!tc.currentChannel) {
_337            return;
_337        }
_337        if (tc.currentChannel.sid === tc.generalChannel.sid) {
_337            alert('You cannot delete the general channel');
_337            return;
_337        }
_337        tc.currentChannel.delete().then(function (channel) {
_337            console.log('channel: ' + channel.friendlyName + ' deleted');
_337            setupChannel(tc.generalChannel);
_337        });
_337    }
_337
_337    function selectChannel(event) {
_337        var target = $(event.target);
_337        var channelSid = target.data().sid;
_337        var selectedChannel = tc.channelArray.filter(function (channel) {
_337            return channel.sid === channelSid;
_337        })[0];
_337        if (selectedChannel === tc.currentChannel) {
_337            return;
_337        }
_337        setupChannel(selectedChannel);
_337    };
_337
_337    function disconnectClient() {
_337        leaveCurrentChannel();
_337        $channelList.text('');
_337        tc.$messageList.text('');
_337        channels = undefined;
_337        $statusRow.addClass('disconnected').removeClass('connected');
_337        tc.$messageList.addClass('disconnected').removeClass('connected');
_337        $connectPanel.addClass('disconnected').removeClass('connected');
_337        $inputText.removeClass('with-shadow');
_337        $typingRow.addClass('disconnected').removeClass('connected');
_337    }
_337
_337    tc.sortChannelsByName = function (channels) {
_337        return channels.sort(function (a, b) {
_337            if (a.friendlyName === GENERAL_CHANNEL_NAME) {
_337                return -1;
_337            }
_337            if (b.friendlyName === GENERAL_CHANNEL_NAME) {
_337                return 1;
_337            }
_337            return a.friendlyName.localeCompare(b.friendlyName);
_337        });
_337    };
_337
_337    return tc;
_337})();

Next, we will see how we can switch between channels.

Join Other Channels

When you tap on the name of a channel from the sidebar, that channel is set as the selectedChannel. The selectChannel method takes care of joining to the selected channel and setting up the selectedChannel.

Join Other Channels

TwilioChat.Web/Scripts/twiliochat.js


_337var twiliochat = (function () {
_337    var tc = {};
_337
_337    var GENERAL_CHANNEL_UNIQUE_NAME = 'general';
_337    var GENERAL_CHANNEL_NAME = 'General Channel';
_337    var MESSAGES_HISTORY_LIMIT = 50;
_337
_337    var $channelList;
_337    var $inputText;
_337    var $usernameInput;
_337    var $statusRow;
_337    var $connectPanel;
_337    var $newChannelInputRow;
_337    var $newChannelInput;
_337    var $typingRow;
_337    var $typingPlaceholder;
_337
_337    $(document).ready(function () {
_337        tc.$messageList = $('#message-list');
_337        $channelList = $('#channel-list');
_337        $inputText = $('#input-text');
_337        $usernameInput = $('#username-input');
_337        $statusRow = $('#status-row');
_337        $connectPanel = $('#connect-panel');
_337        $newChannelInputRow = $('#new-channel-input-row');
_337        $newChannelInput = $('#new-channel-input');
_337        $typingRow = $('#typing-row');
_337        $typingPlaceholder = $('#typing-placeholder');
_337        $usernameInput.focus();
_337        $usernameInput.on('keypress', handleUsernameInputKeypress);
_337        $inputText.on('keypress', handleInputTextKeypress);
_337        $newChannelInput.on('keypress', tc.handleNewChannelInputKeypress);
_337        $('#connect-image').on('click', connectClientWithUsername);
_337        $('#add-channel-image').on('click', showAddChannelInput);
_337        $('#leave-span').on('click', disconnectClient);
_337        $('#delete-channel-span').on('click', deleteCurrentChannel);
_337    });
_337
_337    function handleUsernameInputKeypress(event) {
_337        if (event.keyCode === 13) {
_337            connectClientWithUsername();
_337        }
_337    }
_337
_337    function handleInputTextKeypress(event) {
_337        if (event.keyCode === 13) {
_337            tc.currentChannel.sendMessage($(this).val());
_337            event.preventDefault();
_337            $(this).val('');
_337        }
_337        else {
_337            notifyTyping();
_337        }
_337    }
_337
_337    var notifyTyping = $.throttle(function () {
_337        tc.currentChannel.typing();
_337    }, 1000);
_337
_337    tc.handleNewChannelInputKeypress = function (event) {
_337        if (event.keyCode === 13) {
_337            tc.messagingClient.createChannel({
_337                friendlyName: $newChannelInput.val()
_337            }).then(hideAddChannelInput);
_337            $(this).val('');
_337            event.preventDefault();
_337        }
_337    };
_337
_337    function connectClientWithUsername() {
_337        var usernameText = $usernameInput.val();
_337        $usernameInput.val('');
_337        if (usernameText == '') {
_337            alert('Username cannot be empty');
_337            return;
_337        }
_337        tc.username = usernameText;
_337        fetchAccessToken(tc.username, connectMessagingClient);
_337    }
_337
_337    function fetchAccessToken(username, handler) {
_337        $.post('/token', {
_337            identity: username,
_337            device: 'browser'
_337        }, function (data) {
_337            handler(data);
_337        }, 'json');
_337    }
_337
_337    function connectMessagingClient(tokenResponse) {
_337        // Initialize the IP messaging client
_337        tc.accessManager = new Twilio.AccessManager(tokenResponse.token);
_337        tc.messagingClient = new Twilio.IPMessaging.Client(tc.accessManager);
_337        updateConnectedUI();
_337        tc.loadChannelList(tc.joinGeneralChannel);
_337        tc.messagingClient.on('channelAdded', $.throttle(tc.loadChannelList));
_337        tc.messagingClient.on('channelRemoved', $.throttle(tc.loadChannelList));
_337        tc.messagingClient.on('tokenExpired', refreshToken);
_337    }
_337
_337    function refreshToken() {
_337        fetchAccessToken(tc.username, setNewToken);
_337    }
_337
_337    function setNewToken(tokenResponse) {
_337        tc.accessManager.updateToken(tokenResponse.token);
_337    }
_337
_337    function updateConnectedUI() {
_337        $('#username-span').text(tc.username);
_337        $statusRow.addClass('connected').removeClass('disconnected');
_337        tc.$messageList.addClass('connected').removeClass('disconnected');
_337        $connectPanel.addClass('connected').removeClass('disconnected');
_337        $inputText.addClass('with-shadow');
_337        $typingRow.addClass('connected').removeClass('disconnected');
_337    }
_337
_337    tc.loadChannelList = function (handler) {
_337        if (tc.messagingClient === undefined) {
_337            console.log('Client is not initialized');
_337            return;
_337        }
_337
_337        tc.messagingClient.getChannels().then(function (channels) {
_337            tc.channelArray = tc.sortChannelsByName(channels);
_337            $channelList.text('');
_337            tc.channelArray.forEach(addChannel);
_337            if (typeof handler === 'function') {
_337                handler();
_337            }
_337        });
_337    };
_337
_337    tc.joinGeneralChannel = function () {
_337        console.log('Attempting to join "general" chat channel...');
_337        if (!tc.generalChannel) {
_337            // If it doesn't exist, let's create it
_337            tc.messagingClient.createChannel({
_337                uniqueName: GENERAL_CHANNEL_UNIQUE_NAME,
_337                friendlyName: GENERAL_CHANNEL_NAME
_337            }).then(function (channel) {
_337                console.log('Created general channel');
_337                tc.generalChannel = channel;
_337                tc.loadChannelList(tc.joinGeneralChannel);
_337            });
_337        }
_337        else {
_337            console.log('Found general channel:');
_337            setupChannel(tc.generalChannel);
_337        }
_337    };
_337
_337    function setupChannel(channel) {
_337        // Join the channel
_337        channel.join().then(function (joinedChannel) {
_337            console.log('Joined channel ' + joinedChannel.friendlyName);
_337            leaveCurrentChannel();
_337            updateChannelUI(channel);
_337            tc.currentChannel = channel;
_337            tc.loadMessages();
_337            channel.on('messageAdded', tc.addMessageToList);
_337            channel.on('typingStarted', showTypingStarted);
_337            channel.on('typingEnded', hideTypingStarted);
_337            channel.on('memberJoined', notifyMemberJoined);
_337            channel.on('memberLeft', notifyMemberLeft);
_337            $inputText.prop('disabled', false).focus();
_337            tc.$messageList.text('');
_337        });
_337    }
_337
_337    tc.loadMessages = function () {
_337        tc.currentChannel.getMessages(MESSAGES_HISTORY_LIMIT).then(function (messages) {
_337            messages.forEach(tc.addMessageToList);
_337        });
_337    };
_337
_337    function leaveCurrentChannel() {
_337        if (tc.currentChannel) {
_337            tc.currentChannel.leave().then(function (leftChannel) {
_337                console.log('left ' + leftChannel.friendlyName);
_337                leftChannel.removeListener('messageAdded', tc.addMessageToList);
_337                leftChannel.removeListener('typingStarted', showTypingStarted);
_337                leftChannel.removeListener('typingEnded', hideTypingStarted);
_337                leftChannel.removeListener('memberJoined', notifyMemberJoined);
_337                leftChannel.removeListener('memberLeft', notifyMemberLeft);
_337            });
_337        }
_337    }
_337
_337    tc.addMessageToList = function (message) {
_337        var rowDiv = $('<div>').addClass('row no-margin');
_337        rowDiv.loadTemplate($('#message-template'), {
_337            username: message.author,
_337            date: dateFormatter.getTodayDate(message.timestamp),
_337            body: message.body
_337        });
_337        if (message.author === tc.username) {
_337            rowDiv.addClass('own-message');
_337        }
_337
_337        tc.$messageList.append(rowDiv);
_337        scrollToMessageListBottom();
_337    };
_337
_337    function notifyMemberJoined(member) {
_337        notify(member.identity + ' joined the channel')
_337    }
_337
_337    function notifyMemberLeft(member) {
_337        notify(member.identity + ' left the channel');
_337    }
_337
_337    function notify(message) {
_337        var row = $('<div>').addClass('col-md-12');
_337        row.loadTemplate('#member-notification-template', {
_337            status: message
_337        });
_337        tc.$messageList.append(row);
_337        scrollToMessageListBottom();
_337    }
_337
_337    function showTypingStarted(member) {
_337        $typingPlaceholder.text(member.identity + ' is typing...');
_337    }
_337
_337    function hideTypingStarted(member) {
_337        $typingPlaceholder.text('');
_337    }
_337
_337    function scrollToMessageListBottom() {
_337        tc.$messageList.scrollTop(tc.$messageList[0].scrollHeight);
_337    }
_337
_337    function updateChannelUI(selectedChannel) {
_337        var channelElements = $('.channel-element').toArray();
_337        var channelElement = channelElements.filter(function (element) {
_337            return $(element).data().sid === selectedChannel.sid;
_337        });
_337        channelElement = $(channelElement);
_337        if (tc.currentChannelContainer === undefined && selectedChannel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_337            tc.currentChannelContainer = channelElement;
_337        }
_337        tc.currentChannelContainer.removeClass('selected-channel').addClass('unselected-channel');
_337        channelElement.removeClass('unselected-channel').addClass('selected-channel');
_337        tc.currentChannelContainer = channelElement;
_337    }
_337
_337    function showAddChannelInput() {
_337        if (tc.messagingClient) {
_337            $newChannelInputRow.addClass('showing').removeClass('not-showing');
_337            $channelList.addClass('showing').removeClass('not-showing');
_337            $newChannelInput.focus();
_337        }
_337    }
_337
_337    function hideAddChannelInput() {
_337        $newChannelInputRow.addClass('not-showing').removeClass('showing');
_337        $channelList.addClass('not-showing').removeClass('showing');
_337        $newChannelInput.val('');
_337    }
_337
_337    function addChannel(channel) {
_337        if (channel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_337            tc.generalChannel = channel;
_337        }
_337        var rowDiv = $('<div>').addClass('row channel-row');
_337        rowDiv.loadTemplate('#channel-template', {
_337            channelName: channel.friendlyName
_337        });
_337
_337        var channelP = rowDiv.children().children().first();
_337
_337        rowDiv.on('click', selectChannel);
_337        channelP.data('sid', channel.sid);
_337        if (tc.currentChannel && channel.sid === tc.currentChannel.sid) {
_337            tc.currentChannelContainer = channelP;
_337            channelP.addClass('selected-channel');
_337        }
_337        else {
_337            channelP.addClass('unselected-channel')
_337        }
_337
_337        $channelList.append(rowDiv);
_337    }
_337
_337    function deleteCurrentChannel() {
_337        if (!tc.currentChannel) {
_337            return;
_337        }
_337        if (tc.currentChannel.sid === tc.generalChannel.sid) {
_337            alert('You cannot delete the general channel');
_337            return;
_337        }
_337        tc.currentChannel.delete().then(function (channel) {
_337            console.log('channel: ' + channel.friendlyName + ' deleted');
_337            setupChannel(tc.generalChannel);
_337        });
_337    }
_337
_337    function selectChannel(event) {
_337        var target = $(event.target);
_337        var channelSid = target.data().sid;
_337        var selectedChannel = tc.channelArray.filter(function (channel) {
_337            return channel.sid === channelSid;
_337        })[0];
_337        if (selectedChannel === tc.currentChannel) {
_337            return;
_337        }
_337        setupChannel(selectedChannel);
_337    };
_337
_337    function disconnectClient() {
_337        leaveCurrentChannel();
_337        $channelList.text('');
_337        tc.$messageList.text('');
_337        channels = undefined;
_337        $statusRow.addClass('disconnected').removeClass('connected');
_337        tc.$messageList.addClass('disconnected').removeClass('connected');
_337        $connectPanel.addClass('disconnected').removeClass('connected');
_337        $inputText.removeClass('with-shadow');
_337        $typingRow.addClass('disconnected').removeClass('connected');
_337    }
_337
_337    tc.sortChannelsByName = function (channels) {
_337        return channels.sort(function (a, b) {
_337            if (a.friendlyName === GENERAL_CHANNEL_NAME) {
_337                return -1;
_337            }
_337            if (b.friendlyName === GENERAL_CHANNEL_NAME) {
_337                return 1;
_337            }
_337            return a.friendlyName.localeCompare(b.friendlyName);
_337        });
_337    };
_337
_337    return tc;
_337})();

At some point your users will want to delete a channel. Let's have a look at how that can be done.

Delete a Channel

Deleting a channel is even more simple than creating one. The application lets the user delete the channel they are currently joined to through the "delete current channel" link. The only thing you need to do to actually delete the channel from Twilio, is call the delete method on the channel you are trying to delete. As other methods on the `Channel' object, It'll return a promise where you can set function that is going to handle successes.

Delete a Channel

TwilioChat.Web/Scripts/twiliochat.js


_337var twiliochat = (function () {
_337    var tc = {};
_337
_337    var GENERAL_CHANNEL_UNIQUE_NAME = 'general';
_337    var GENERAL_CHANNEL_NAME = 'General Channel';
_337    var MESSAGES_HISTORY_LIMIT = 50;
_337
_337    var $channelList;
_337    var $inputText;
_337    var $usernameInput;
_337    var $statusRow;
_337    var $connectPanel;
_337    var $newChannelInputRow;
_337    var $newChannelInput;
_337    var $typingRow;
_337    var $typingPlaceholder;
_337
_337    $(document).ready(function () {
_337        tc.$messageList = $('#message-list');
_337        $channelList = $('#channel-list');
_337        $inputText = $('#input-text');
_337        $usernameInput = $('#username-input');
_337        $statusRow = $('#status-row');
_337        $connectPanel = $('#connect-panel');
_337        $newChannelInputRow = $('#new-channel-input-row');
_337        $newChannelInput = $('#new-channel-input');
_337        $typingRow = $('#typing-row');
_337        $typingPlaceholder = $('#typing-placeholder');
_337        $usernameInput.focus();
_337        $usernameInput.on('keypress', handleUsernameInputKeypress);
_337        $inputText.on('keypress', handleInputTextKeypress);
_337        $newChannelInput.on('keypress', tc.handleNewChannelInputKeypress);
_337        $('#connect-image').on('click', connectClientWithUsername);
_337        $('#add-channel-image').on('click', showAddChannelInput);
_337        $('#leave-span').on('click', disconnectClient);
_337        $('#delete-channel-span').on('click', deleteCurrentChannel);
_337    });
_337
_337    function handleUsernameInputKeypress(event) {
_337        if (event.keyCode === 13) {
_337            connectClientWithUsername();
_337        }
_337    }
_337
_337    function handleInputTextKeypress(event) {
_337        if (event.keyCode === 13) {
_337            tc.currentChannel.sendMessage($(this).val());
_337            event.preventDefault();
_337            $(this).val('');
_337        }
_337        else {
_337            notifyTyping();
_337        }
_337    }
_337
_337    var notifyTyping = $.throttle(function () {
_337        tc.currentChannel.typing();
_337    }, 1000);
_337
_337    tc.handleNewChannelInputKeypress = function (event) {
_337        if (event.keyCode === 13) {
_337            tc.messagingClient.createChannel({
_337                friendlyName: $newChannelInput.val()
_337            }).then(hideAddChannelInput);
_337            $(this).val('');
_337            event.preventDefault();
_337        }
_337    };
_337
_337    function connectClientWithUsername() {
_337        var usernameText = $usernameInput.val();
_337        $usernameInput.val('');
_337        if (usernameText == '') {
_337            alert('Username cannot be empty');
_337            return;
_337        }
_337        tc.username = usernameText;
_337        fetchAccessToken(tc.username, connectMessagingClient);
_337    }
_337
_337    function fetchAccessToken(username, handler) {
_337        $.post('/token', {
_337            identity: username,
_337            device: 'browser'
_337        }, function (data) {
_337            handler(data);
_337        }, 'json');
_337    }
_337
_337    function connectMessagingClient(tokenResponse) {
_337        // Initialize the IP messaging client
_337        tc.accessManager = new Twilio.AccessManager(tokenResponse.token);
_337        tc.messagingClient = new Twilio.IPMessaging.Client(tc.accessManager);
_337        updateConnectedUI();
_337        tc.loadChannelList(tc.joinGeneralChannel);
_337        tc.messagingClient.on('channelAdded', $.throttle(tc.loadChannelList));
_337        tc.messagingClient.on('channelRemoved', $.throttle(tc.loadChannelList));
_337        tc.messagingClient.on('tokenExpired', refreshToken);
_337    }
_337
_337    function refreshToken() {
_337        fetchAccessToken(tc.username, setNewToken);
_337    }
_337
_337    function setNewToken(tokenResponse) {
_337        tc.accessManager.updateToken(tokenResponse.token);
_337    }
_337
_337    function updateConnectedUI() {
_337        $('#username-span').text(tc.username);
_337        $statusRow.addClass('connected').removeClass('disconnected');
_337        tc.$messageList.addClass('connected').removeClass('disconnected');
_337        $connectPanel.addClass('connected').removeClass('disconnected');
_337        $inputText.addClass('with-shadow');
_337        $typingRow.addClass('connected').removeClass('disconnected');
_337    }
_337
_337    tc.loadChannelList = function (handler) {
_337        if (tc.messagingClient === undefined) {
_337            console.log('Client is not initialized');
_337            return;
_337        }
_337
_337        tc.messagingClient.getChannels().then(function (channels) {
_337            tc.channelArray = tc.sortChannelsByName(channels);
_337            $channelList.text('');
_337            tc.channelArray.forEach(addChannel);
_337            if (typeof handler === 'function') {
_337                handler();
_337            }
_337        });
_337    };
_337
_337    tc.joinGeneralChannel = function () {
_337        console.log('Attempting to join "general" chat channel...');
_337        if (!tc.generalChannel) {
_337            // If it doesn't exist, let's create it
_337            tc.messagingClient.createChannel({
_337                uniqueName: GENERAL_CHANNEL_UNIQUE_NAME,
_337                friendlyName: GENERAL_CHANNEL_NAME
_337            }).then(function (channel) {
_337                console.log('Created general channel');
_337                tc.generalChannel = channel;
_337                tc.loadChannelList(tc.joinGeneralChannel);
_337            });
_337        }
_337        else {
_337            console.log('Found general channel:');
_337            setupChannel(tc.generalChannel);
_337        }
_337    };
_337
_337    function setupChannel(channel) {
_337        // Join the channel
_337        channel.join().then(function (joinedChannel) {
_337            console.log('Joined channel ' + joinedChannel.friendlyName);
_337            leaveCurrentChannel();
_337            updateChannelUI(channel);
_337            tc.currentChannel = channel;
_337            tc.loadMessages();
_337            channel.on('messageAdded', tc.addMessageToList);
_337            channel.on('typingStarted', showTypingStarted);
_337            channel.on('typingEnded', hideTypingStarted);
_337            channel.on('memberJoined', notifyMemberJoined);
_337            channel.on('memberLeft', notifyMemberLeft);
_337            $inputText.prop('disabled', false).focus();
_337            tc.$messageList.text('');
_337        });
_337    }
_337
_337    tc.loadMessages = function () {
_337        tc.currentChannel.getMessages(MESSAGES_HISTORY_LIMIT).then(function (messages) {
_337            messages.forEach(tc.addMessageToList);
_337        });
_337    };
_337
_337    function leaveCurrentChannel() {
_337        if (tc.currentChannel) {
_337            tc.currentChannel.leave().then(function (leftChannel) {
_337                console.log('left ' + leftChannel.friendlyName);
_337                leftChannel.removeListener('messageAdded', tc.addMessageToList);
_337                leftChannel.removeListener('typingStarted', showTypingStarted);
_337                leftChannel.removeListener('typingEnded', hideTypingStarted);
_337                leftChannel.removeListener('memberJoined', notifyMemberJoined);
_337                leftChannel.removeListener('memberLeft', notifyMemberLeft);
_337            });
_337        }
_337    }
_337
_337    tc.addMessageToList = function (message) {
_337        var rowDiv = $('<div>').addClass('row no-margin');
_337        rowDiv.loadTemplate($('#message-template'), {
_337            username: message.author,
_337            date: dateFormatter.getTodayDate(message.timestamp),
_337            body: message.body
_337        });
_337        if (message.author === tc.username) {
_337            rowDiv.addClass('own-message');
_337        }
_337
_337        tc.$messageList.append(rowDiv);
_337        scrollToMessageListBottom();
_337    };
_337
_337    function notifyMemberJoined(member) {
_337        notify(member.identity + ' joined the channel')
_337    }
_337
_337    function notifyMemberLeft(member) {
_337        notify(member.identity + ' left the channel');
_337    }
_337
_337    function notify(message) {
_337        var row = $('<div>').addClass('col-md-12');
_337        row.loadTemplate('#member-notification-template', {
_337            status: message
_337        });
_337        tc.$messageList.append(row);
_337        scrollToMessageListBottom();
_337    }
_337
_337    function showTypingStarted(member) {
_337        $typingPlaceholder.text(member.identity + ' is typing...');
_337    }
_337
_337    function hideTypingStarted(member) {
_337        $typingPlaceholder.text('');
_337    }
_337
_337    function scrollToMessageListBottom() {
_337        tc.$messageList.scrollTop(tc.$messageList[0].scrollHeight);
_337    }
_337
_337    function updateChannelUI(selectedChannel) {
_337        var channelElements = $('.channel-element').toArray();
_337        var channelElement = channelElements.filter(function (element) {
_337            return $(element).data().sid === selectedChannel.sid;
_337        });
_337        channelElement = $(channelElement);
_337        if (tc.currentChannelContainer === undefined && selectedChannel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_337            tc.currentChannelContainer = channelElement;
_337        }
_337        tc.currentChannelContainer.removeClass('selected-channel').addClass('unselected-channel');
_337        channelElement.removeClass('unselected-channel').addClass('selected-channel');
_337        tc.currentChannelContainer = channelElement;
_337    }
_337
_337    function showAddChannelInput() {
_337        if (tc.messagingClient) {
_337            $newChannelInputRow.addClass('showing').removeClass('not-showing');
_337            $channelList.addClass('showing').removeClass('not-showing');
_337            $newChannelInput.focus();
_337        }
_337    }
_337
_337    function hideAddChannelInput() {
_337        $newChannelInputRow.addClass('not-showing').removeClass('showing');
_337        $channelList.addClass('not-showing').removeClass('showing');
_337        $newChannelInput.val('');
_337    }
_337
_337    function addChannel(channel) {
_337        if (channel.uniqueName === GENERAL_CHANNEL_UNIQUE_NAME) {
_337            tc.generalChannel = channel;
_337        }
_337        var rowDiv = $('<div>').addClass('row channel-row');
_337        rowDiv.loadTemplate('#channel-template', {
_337            channelName: channel.friendlyName
_337        });
_337
_337        var channelP = rowDiv.children().children().first();
_337
_337        rowDiv.on('click', selectChannel);
_337        channelP.data('sid', channel.sid);
_337        if (tc.currentChannel && channel.sid === tc.currentChannel.sid) {
_337            tc.currentChannelContainer = channelP;
_337            channelP.addClass('selected-channel');
_337        }
_337        else {
_337            channelP.addClass('unselected-channel')
_337        }
_337
_337        $channelList.append(rowDiv);
_337    }
_337
_337    function deleteCurrentChannel() {
_337        if (!tc.currentChannel) {
_337            return;
_337        }
_337        if (tc.currentChannel.sid === tc.generalChannel.sid) {
_337            alert('You cannot delete the general channel');
_337            return;
_337        }
_337        tc.currentChannel.delete().then(function (channel) {
_337            console.log('channel: ' + channel.friendlyName + ' deleted');
_337            setupChannel(tc.generalChannel);
_337        });
_337    }
_337
_337    function selectChannel(event) {
_337        var target = $(event.target);
_337        var channelSid = target.data().sid;
_337        var selectedChannel = tc.channelArray.filter(function (channel) {
_337            return channel.sid === channelSid;
_337        })[0];
_337        if (selectedChannel === tc.currentChannel) {
_337            return;
_337        }
_337        setupChannel(selectedChannel);
_337    };
_337
_337    function disconnectClient() {
_337        leaveCurrentChannel();
_337        $channelList.text('');
_337        tc.$messageList.text('');
_337        channels = undefined;
_337        $statusRow.addClass('disconnected').removeClass('connected');
_337        tc.$messageList.addClass('disconnected').removeClass('connected');
_337        $connectPanel.addClass('disconnected').removeClass('connected');
_337        $inputText.removeClass('with-shadow');
_337        $typingRow.addClass('disconnected').removeClass('connected');
_337    }
_337
_337    tc.sortChannelsByName = function (channels) {
_337        return channels.sort(function (a, b) {
_337            if (a.friendlyName === GENERAL_CHANNEL_NAME) {
_337                return -1;
_337            }
_337            if (b.friendlyName === GENERAL_CHANNEL_NAME) {
_337                return 1;
_337            }
_337            return a.friendlyName.localeCompare(b.friendlyName);
_337        });
_337    };
_337
_337    return tc;
_337})();

That's it! We've just implemented a simple chat application for C# using ASP.NET MVC.

Where to Next?

If you are a C# developer working with Twilio, you might want to check out these other tutorials:

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Masked Phone Numbers

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Did this help?

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