private void btnListen_Click(object sender, EventArgs e)
{
    IPEndPoint point = new IPEndPoint(IPAddress.Any, 13000);//IPAddress.Any本機任何網(wǎng)卡IP。本機端口查看netstat -an
    //服務端Socket定義
    Socket socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
    socket.Bind(point); //綁定IP
    socket.Listen(10);//啟動監(jiān)聽。最大監(jiān)聽數(shù),同一個時間點過來10個客戶端，排隊
    ShowMsg("服務器開始監(jiān)聽");

    Thread thread = new Thread(AcceptInfo);
    thread.Start(socket);

}

//記錄通信用的Socket
Dictionary<string, Socket> dic = new Dictionary<string, Socket>();

// private Socket client;
void AcceptInfo(object o)
{
    Socket socket = o as Socket;
    while (true)
    {
        //通信用socket
        try
        {
            Socket clientSocket = socket.Accept();//如果客戶端有請求，生成一個新的Socket
            string point = clientSocket.RemoteEndPoint.ToString();
            ShowMsg(point + "連接客戶端成功！");
            dic.Add(point, clientSocket);
            //接收消息
            Thread th = new Thread(ReceiveMsg);
            th.Start(clientSocket);
        }
        catch (Exception ex)
        {
            break;
        }
    }
    socket.Close();
}
//接收消息
void ReceiveMsg(object socket)
{
    Socket clientSocket = socket as Socket;
    while (true)
    {
        //接收客戶端發(fā)送過來的數(shù)據(jù)
        try
        {
            //定義byte數(shù)組存放從客戶端接收過來的數(shù)據(jù)
            byte[] buffer = new byte[1024 * 1024];
            
           int n = clientSocket.Receive(buffer);//將接收過來的數(shù)據(jù)放到buffer中，并返回實際接受數(shù)據(jù)的長度

            //將字節(jié)轉換成字符串
            string words = Encoding.Unicode.GetString(buffer, 0, n);
            Console.WriteLine(clientSocket.RemoteEndPoint.ToString() + ":" + words);
            byte[] msg = Encoding.Unicode.GetBytes(words);
            clientSocket.Send(msg);//發(fā)送數(shù)據(jù)，字節(jié)數(shù)組
        }
        catch (Exception ex)
        {
            break;
        }
    }
    clientSocket.Shutdown(SocketShutdown.Both);//禁止發(fā)送和接受數(shù)據(jù)
    clientSocket.Close();//關閉socket,釋放資源
}

Socket clientSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
IPEndPoint point = new IPEndPoint("127.0.0.1", 13000));//連接到的服務端IP
clientSocket.Connect(point);//連接到服務器
ShowMsg("連接成功");
ShowMsg("服務器" + client.RemoteEndPoint.ToString());
ShowMsg("客戶端:" + client.LocalEndPoint.ToString());
Thread th = new Thread(ReceiveMsg);//連接成功后，就可以接收服務器發(fā)送的信息了
th.IsBackground = true;
th.Start();

clientSocket.Shutdown(SocketShutdown.Both);//禁止發(fā)送和接受數(shù)據(jù)
clientSocket.Close();//關閉socket,釋放資源