If you want to use the WebSocket API, it is useful if you have a server. :-) In this article I will show you how to write one in C#.
In lots of server side programming language you can do it, but to keep things simple and more understandable, I chose Microsoft's language.
This server gives which is required by RFC 6455 so it will only handle connections from Chrome version 16, Firefox 11, IE 10 and over.
It is a good idea to use using keyword to write less. It means you have not to retype the name of namespace if you use classes from it.
Constructor of it looks like this:
TcpListener(IPAddress localaddr, int port)