Websocket server: onopen function on the web socket is never called

I'm trying to implement a C# web socket server, but its giving me a few troubles. I'm running a webserver(ASP.NET) to host the page with the javascript and the web socket server is implemented as a C# console application.

I'm able to detect the connection attempt from the client (chrome running the javascript) and also to retrieve the handshake from the client. But the client doesn't seem to accept the handshake I'm sending back (the onopen function on the web socket is never called).

I've been reading the The Web Socket protocol and I can't see what I'm doing wrong. Heres a bit of the server code:

Socket listener = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.IP);
IPEndPoint ep = new IPEndPoint(IPAddress.Parse("127.0.0.1"), 8181);
listener.Bind(ep);
listener.Listen(100);
Console.WriteLine("Wainting for connection...");
Socket socketForClient = listener.Accept();
if (socketForClient.Connected)
{
    Console.WriteLine("Client connected");
    NetworkStream networkStream = new NetworkStream(socketForClient);
    System.IO.StreamWriter streamWriter = new System.IO.StreamWriter(networkStream);
    System.IO.StreamReader streamReader = new System.IO.StreamReader(networkStream);

    //read handshake from client:
    Console.WriteLine("HANDSHAKING...");
    char[] shake = new char[255];
    streamReader.Read(shake, 0, 255);

    string handshake =
       "HTTP/1.1 101 Web Socket Protocol Handshake\r\n" +
       "Upgrade: WebSocket\r\n" +
       "Connection: Upgrade\r\n" +
       "WebSocket-Origin: http://localhost:8080\r\n" +
       "WebSocket-Location: ws://localhost:8181\r\n" +
       "\r\n";

    streamWriter.Write(handshake);
    streamWriter.Flush();

I'm running to web s

c# websocket

Edit Report

Probably it's an encoding issue. Here's a working C# server I wrote:

class Program
{
    static void Main(string[] args)
    {
        var listener = new TcpListener(IPAddress.Loopback, 8181);
        listener.Start();
        using (var client = listener.AcceptTcpClient())
        using (var stream = client.GetStream())
        using (var reader = new StreamReader(stream))
        using (var writer = new StreamWriter(stream))
        {
            writer.WriteLine("HTTP/1.1 101 Web Socket Protocol Handshake");
            writer.WriteLine("Upgrade: WebSocket");
            writer.WriteLine("Connection: Upgrade");
            writer.WriteLine("WebSocket-Origin: http://localhost:8080");
            writer.WriteLine("WebSocket-Location: ws://localhost:8181/websession");
            writer.WriteLine("");
        }
        listener.Stop();
    }
}

And the corresponding client hosted on localhost:8080:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" 
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
  <head>
    <script type="text/javascript">
      var socket = new WebSocket('ws://localhost:8181/websession');
      socket.onopen = function() {
        alert('handshake successfully established. May send data now...');
      };
      socket.onclose = function() {
        alert('connection closed');
      };
    </script>
  </head>
  <body>
  </body>
</html>

This example only establishes the handshake. You will need to tweak the server in order to continue accepting data once the handshake has been established.

answered 2010-02-06T10:07:41.677

Websocket server: onopen function on the web socket is never called

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