prabirshrestha/default.aspx

## readme
Sample echo server written in asp.net 4.5.

This sample must be run on full IIS and requires Win8 Beta with WebSockets enabled in IIS.

## default.aspx
<%@ Page Language="C#" %>

<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
    <title></title>
</head>
<body>

    <form id="form1" runat="server">
        <input type="text" id="message"/>
        <input type="button" value="send" id="send"/>
        <div id='messages'></div>
    </form>

    <script type="text/javascript">
        var socket,
            $txt = document.getElementById('message'),
            $messages = document.getElementById('messages');

        if (typeof (WebSocket) !== 'undefined') {
            socket = new WebSocket("ws://localhost/WebSocketHelloEchoServer/echo.ashx");
        } else {
            socket = new MozWebSocket("ws://localhost/WebSocketHelloEchoServer/echo.ashx");
        }

        socket.onmessage = function (msg) {
            var $el = document.createElement('p');
            $el.innerHTML = msg.data;
            $messages.appendChild($el);
        };

        document.getElementById('send').onclick = function () {
            socket.send($txt.value);
        };
    </script>
</body>
</html>

## echo.ashx
<%@ WebHandler Language="C#" CodeBehind="echo.ashx.cs" Class="WebSocketHelloEchoServer.echo" %>

## echo.ashx.cs

using System;
using System.Collections.Generic;
using System.Net.WebSockets;
using System.Threading;
using System.Threading.Tasks;
using System.Web;
using System.Web.WebSockets;

namespace WebSocketHelloEchoServer
{
    /// <summary>
    /// Summary description for echo
    /// </summary>
    /// <remarks>http://evolpin.wordpress.com/2012/02/17/html5-websockets-revolution/</remarks>
    public class echo : IHttpHandler
    {
        // list of client WebSockets that are open
        private static readonly IList<WebSocket> Clients = new List<WebSocket>();

        // ensure thread-safety of the WebSocket clients
        private static readonly ReaderWriterLockSlim Locker = new ReaderWriterLockSlim();

        public void ProcessRequest(HttpContext context)
        {
            ProcessRequest(new HttpContextWrapper(context));
        }

        public void ProcessRequest(HttpContextBase context)
        {
            if (context.IsWebSocketRequest)
                context.AcceptWebSocketRequest(ProcessSocketRequest);
        }

        private async Task ProcessSocketRequest(AspNetWebSocketContext context)
        {
            var socket = context.WebSocket;

            // add socket to socket list
            Locker.EnterWriteLock();
            try
            {
                Clients.Add(socket);
            }
            finally
            {
                Locker.ExitWriteLock();
            }

            // maintain socket
            while (true)
            {
                var buffer = new ArraySegment<byte>(new byte[1024]);

                // async wait for a change in the socket
                var result = await socket.ReceiveAsync(buffer, CancellationToken.None);

                if (socket.State == WebSocketState.Open)
                {
                    // echo to all clients
                    foreach (var client in Clients)
                    {
                        await client.SendAsync(buffer, WebSocketMessageType.Text, true, CancellationToken.None);
                    }
                }
                else
                {
                    // client is no longer available - delete from list
                    Locker.EnterWriteLock();
                    try
                    {
                        Clients.Remove(socket);
                    }
                    finally
                    {
                        Locker.ExitWriteLock();
                    }

                    break;

                }
            }
        }

        public bool IsReusable
        {
            get
            {
                return false;
            }
        }
    }
}
	Sample echo server written in asp.net 4.5.

	This sample must be run on full IIS and requires Win8 Beta with WebSockets enabled in IIS.
	<%@ Page Language="C#" %>

	<!DOCTYPE html>
	<html xmlns="http://www.w3.org/1999/xhtml">
	<head id="Head1" runat="server">
	<title></title>
	</head>
	<body>

	<form id="form1" runat="server">
	<input type="text" id="message"/>
	<input type="button" value="send" id="send"/>
	<div id='messages'></div>
	</form>

	<script type="text/javascript">
	var socket,
	$txt = document.getElementById('message'),
	$messages = document.getElementById('messages');

	if (typeof (WebSocket) !== 'undefined') {
	socket = new WebSocket("ws://localhost/WebSocketHelloEchoServer/echo.ashx");
	} else {
	socket = new MozWebSocket("ws://localhost/WebSocketHelloEchoServer/echo.ashx");
	}

	socket.onmessage = function (msg) {
	var $el = document.createElement('p');
	$el.innerHTML = msg.data;
	$messages.appendChild($el);
	};

	document.getElementById('send').onclick = function () {
	socket.send($txt.value);
	};
	</script>
	</body>
	</html>

	using System;
	using System.Collections.Generic;
	using System.Net.WebSockets;
	using System.Threading;
	using System.Threading.Tasks;
	using System.Web;
	using System.Web.WebSockets;

	namespace WebSocketHelloEchoServer
	{
	/// <summary>
	/// Summary description for echo
	/// </summary>
	/// <remarks>http://evolpin.wordpress.com/2012/02/17/html5-websockets-revolution/</remarks>
	public class echo : IHttpHandler
	{
	// list of client WebSockets that are open
	private static readonly IList<WebSocket> Clients = new List<WebSocket>();

	// ensure thread-safety of the WebSocket clients
	private static readonly ReaderWriterLockSlim Locker = new ReaderWriterLockSlim();

	public void ProcessRequest(HttpContext context)
	{
	ProcessRequest(new HttpContextWrapper(context));
	}

	public void ProcessRequest(HttpContextBase context)
	{
	if (context.IsWebSocketRequest)
	context.AcceptWebSocketRequest(ProcessSocketRequest);
	}

	private async Task ProcessSocketRequest(AspNetWebSocketContext context)
	{
	var socket = context.WebSocket;

	// add socket to socket list
	Locker.EnterWriteLock();
	try
	{
	Clients.Add(socket);
	}
	finally
	{
	Locker.ExitWriteLock();
	}

	// maintain socket
	while (true)
	{
	var buffer = new ArraySegment<byte>(new byte[1024]);

	// async wait for a change in the socket
	var result = await socket.ReceiveAsync(buffer, CancellationToken.None);

	if (socket.State == WebSocketState.Open)
	{
	// echo to all clients
	foreach (var client in Clients)
	{
	await client.SendAsync(buffer, WebSocketMessageType.Text, true, CancellationToken.None);
	}
	}
	else
	{
	// client is no longer available - delete from list
	Locker.EnterWriteLock();
	try
	{
	Clients.Remove(socket);
	}
	finally
	{
	Locker.ExitWriteLock();
	}

	break;

	}
	}
	}

	public bool IsReusable
	{
	get
	{
	return false;
	}
	}
	}
	}