class Program
    {
        const string _ip = "192.168.0.125";
        const int duankou = 168;
        static void Main(string[] args)
        {

            Socket serverSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
            IPAddress ipadd = IPAddress.Parse(_ip);
            IPEndPoint ipend = new IPEndPoint(ipadd, duankou);
            serverSocket.Bind(ipend);
            Console.WriteLine("成功创建了一个服务端口!");


            serverSocket.Listen(20);
            Socket socketJs = serverSocket.Accept();
            Console.WriteLine("有个小火伴要连进来;了");

            //接收消息:
            string str = "";
            byte[] strByte = new byte[1024];
            int strLength = socketJs.Receive(strByte, strByte.Length, 0);
            str = Encoding.UTF8.GetString(strByte, 0, strLength);
            Console.WriteLine("接收消息成功!\n");

            Console.WriteLine(str);


            //发送消息:
            string str1 = "老师:小学生是不可以谈恋爱的哦~~~~";
            byte[] strByte1 = Encoding.UTF8.GetBytes(str1);
            socketJs.Send(strByte1);
            Console.WriteLine("向客户端发送消息成功!");

            Console.ReadKey();

        }
    }

 class Program
    {
        const string _ip = "192.168.0.125";
        const int duankou = 168;
        static void Main(string[] args)
        {
            Socket clientSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
            IPAddress ipadd = IPAddress.Parse(_ip);
            IPEndPoint ipend = new IPEndPoint(ipadd, duankou);
            clientSocket.Connect(ipend);
            Console.WriteLine("成功创建了一个客户端Socket!");

            //发送消息:
            string str = "小花:报告老师,小明要跟我表白!\n";
            byte[] strByte = Encoding.UTF8.GetBytes(str);
            clientSocket.Send(strByte);
            Console.WriteLine("发送消息成功!\n");


            //接收消息:
            string str1 = "";
            byte[] strByte1 = new byte[1024];
            int strLength = clientSocket.Receive(strByte1, strByte1.Length, 0);
            str1 = Encoding.UTF8.GetString(strByte1, 0, strLength);
            Console.WriteLine(str1);
            Console.WriteLine("\n接收服务端发来的消息成功!");
            Console.ReadKey();
        }
    }