服务器为每一个连接客户端产生一个线程，这样接受多个连接

//服务器为每一个连接客户端产生一个线程，这样接受多个连接:
private TcpListener tcpListener;
private Thread listenThread;

 public Server()
 {
     this.tcpListener = new TcpListener(IPAddress.Any, 3000);
     this.listenThread = new Thread(new ThreadStart(ListenForClients));
     this.listenThread.Start();
 }

 private void ListenForClients()
 {
     this.tcpListener.Start();
     while (true)
     {
         //blocks until a client has connected to the server
         TcpClient client = this.tcpListener.AcceptTcpClient();

         //create a thread to handle communication
         //with connected client
         Thread clientThread = new Thread(new ParameterizedThreadStart(HandleClientComm));
         clientThread.Start(client);
     }
 }

 private void HandleClientComm(object client)
 {
     TcpClient tcpClient = (TcpClient)client;
     NetworkStream clientStream = tcpClient.GetStream();