A high performance websocket server library powering Stack Overflow.
Latest commit fb135f0 Dec 10, 2016 @mgravell mgravell Fix #13


Welcome to StackExchange.NetGain!

NetGain supports:

  • RFC 6455
  • all draft versions of the RFC (between hixie-76 and v13, aka RFC 6455)
  • hixie-76/hybi-00
  • fixes for various browsers with slightly broken implementations


StackExchange.NetGain is built as a single assembly, StackExchange.NetGain.dll.

NuGet Gallery

StackExchange.NetGain is available on the [NuGet Gallery]

  • [NuGet Gallery: stackexchange.netgain]

You can add StackExchange.NetGain to your project with the NuGet Package Manager, by using the following command in the Package Manager Console.

PM> Install-Package StackExchange.NetGain

WebSocket Server Example

using System;
using System.Net;
using StackExchange.NetGain;
using StackExchange.NetGain.WebSockets;

namespace Example
  public class Program
    public static void Main (string[] args)
        IPEndPoint endpoint = new IPEndPoint(IPAddress.Loopback, 6002);
        using(var server = new TcpServer())
            server.ProtocolFactory = WebSocketsSelectorProcessor.Default;
            server.ConnectionTimeoutSeconds = 60;
            server.Received += msg =>
                var conn = (WebSocketConnection)msg.Connection;
                string reply = (string)msg.Value + " / " + conn.Host;
                Console.WriteLine("[server] {0}", msg.Value);
                msg.Connection.Send(msg.Context, reply);
            server.Start("abc", endpoint);
            Console.WriteLine("Server running");

        Console.WriteLine("Server dead; press any key");