//Server
using System;
 using System.Collections.Generic;
 using System.Text;
 using System.Net;
 using System.Net.Sockets;
 using System.Threading;
 namespace server
 {
     class Program
     {
         static void Main(string[] args)
         {
             int port = 2000;
             string host = "127.0.0.1";            ///创建终结点（EndPoint）
             IPAddress ip = IPAddress.Parse(host);//把ip地址字符串转换为IPAddress类型的实例
             IPEndPoint ipe = new IPEndPoint(ip, port);//用指定的端口和ip初始化IPEndPoint类的新实例            ///创建socket并开始监听
             Socket s = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);//创建一个socket对像，如果用udp协议，则要用SocketType.Dgram类型的套接字
             s.Bind(ipe);//绑定EndPoint对像（2000端口和ip地址）
             s.Listen(0);//开始监听
             Console.WriteLine("等待客户端连接");
             while (true) 
             {
                 ///接受到client连接，为此连接建立新的socket，并接受信息
                 Socket temp = s.Accept();//为新建连接创建新的socket
                 new Thread(new ThreadStart(delegate
                 {
                     Console.WriteLine("建立连接");
                     string recvStr = "";
                     byte[] recvBytes = new byte[1024];
                     int bytes;
                     bytes = temp.Receive(recvBytes, recvBytes.Length, 0);//从客户端接受信息
                     recvStr += Encoding.ASCII.GetString(recvBytes, 0, bytes);                    ///给client端返回信息
                     Console.WriteLine("server get message:{0}", recvStr);//把客户端传来的信息显示出来
                     string sendStr = "ok!Client send message successful!";
                     byte[] bs = Encoding.ASCII.GetBytes(sendStr);
                     temp.Send(bs, bs.Length, 0);//返回信息给客户端
                     temp.Close();
                 })).Start();            }
             s.Close();
             Console.ReadLine();
         }    }
 } //Client
 using System;
 using System.Collections.Generic;
 using System.Text;
 using System.Net;
 using System.Net.Sockets;
 namespace Client
 {
     class Program
     {
         static void Main(string[] args)
         {
             try
             {
                 int port = 2000;
                 string host = "127.0.0.1";
                 ///创建终结点EndPoint
                 IPAddress ip = IPAddress.Parse(host);
                 //IPAddress ipp = new IPAddress("127.0.0.1");
                 IPEndPoint ipe = new IPEndPoint(ip, port);//把ip和端口转化为IPEndpoint实例                ///创建socket并连接到服务器
                 Socket c = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);//创建Socket
                 Console.WriteLine("Conneting…");
                 c.Connect(ipe);//连接到服务器                ///向服务器发送信息
                 string sendStr = "hello!This is a socket test";
                 byte[] bs = Encoding.ASCII.GetBytes(sendStr);//把字符串编码为字节
                 Console.WriteLine("Send Message");
                 c.Send(bs, bs.Length, 0);//发送信息                ///接受从服务器返回的信息
                 string recvStr = "";
                 byte[] recvBytes = new byte[1024];
                 int bytes;
                 bytes = c.Receive(recvBytes, recvBytes.Length, 0);//从服务器端接受返回信息
                 recvStr += Encoding.ASCII.GetString(recvBytes, 0, bytes);
                 Console.WriteLine("client get message:{0}", recvStr);//显示服务器返回信息
                 ///一定记着用完socket后要关闭
                 c.Close();
             }
             catch (ArgumentNullException e)
             {
                 Console.WriteLine("argumentNullException: {0}", e);
             }
             catch (SocketException e)
             {
                 Console.WriteLine("SocketException:{0}", e);
             }
             Console.WriteLine("Press Enter to Exit");
         }
     }
 }