WebSockets is an emerging standard that enables real-time and bidirectional communication across the Web. You will learn how HTML5 web applications can make dramatic improvements in terms of user experience and performance by taking advantage of this technology. In this session we will focus on the new WCF 4.5 and ASP.NET 4.5 APIs supporting this standard.

2. Peter Himschoot
peter@u2u.net
U2U

5. “Real time web” is
awesome!!!
“A real pain to build”

6. Ian Hickson

7. Server
Client
Server
“Comet”
Client

8. a socket that works anywhere across the web
…even through network intermediaries

12. public class GameHttpHandler : IHttpHandler
{
public void ProcessRequest(HttpContext context)
{
if (context.IsWebSocketRequest)
{
var player = new GamePlayer();
FourInABruGame.Join(player);
context.AcceptWebSocketRequest(player.SocketReceiver);
}
}

13. public async Task SocketReceiver(AspNetWebSocketContext context)
{
var socket = context.WebSocket as AspNetWebSocket;
var buffer = new ArraySegment<byte>(new byte[2048]);
while (true) {
var message =
await socket.ReceiveAsync(buffer, CancellationToken.None);
// Convert to JSON
var json = Encoding.UTF8.GetString(buffer.Array, 0, message.Count);
var test = new { type = "" };
test = JsonConvert.DeserializeAnonymousType(json, test);

14. public async Task SendMessage(SocketMessage message)
{
string json = JsonConvert.SerializeObject(message);
var buffer = new ArraySegment<byte>(Encoding.UTF8.GetBytes(json));
await Context.WebSocket.SendAsync(buffer, WebSocketMessageType.Text,
endOfMessage: true, cancellationToken: CancellationToken.None);
}

17. “ws://servername/socket”
“wss://servername/socket”
var ws = new WebSocket(socketUri);
ws.openStateConst = WebSocket.OPEN;

18. ws.onopen = function () {
display('Connected');
}
ws.onmessage = function (json) {
processMessage(json);
}
...

19. ws.send(JSON.stringify({ type: "wins", player: player }));

20. Demo

22. http://aka.ms/mbl-tech
http://aka.ms/mbl-tech/devprev
http://aka.ms/mbl-tech/html5