static void Main(string[] args){  int recv;  byte[] data = new byte[1024];  IPEndPoint ipep = new IPEndPoint(IPAddress.Any, 9050);//定義一網絡端點  Socket newsock = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);//定義一個Socket  newsock.Bind(ipep);//Socket與本地的一個終結點相關聯  Console.WriteLine("Waiting for a client..");  IPEndPoint sender = new IPEndPoint(IPAddress.Any, 0);//定義要發送的計算機的地址  EndPoint Remote = (EndPoint)(sender);//  recv = newsock.ReceiveFrom(data, ref Remote);//接受數據        Console.WriteLine("Message received from{0}:", Remote.ToString());  Console.WriteLine(Encoding.ASCII.GetString(data, 0, recv));  string welcome = "Welcome to my test server!";  data = Encoding.ASCII.GetBytes(welcome);  newsock.SendTo(data, data.Length, SocketFlags.None, Remote);  while (true)  {    data = new byte[1024];    recv = newsock.ReceiveFrom(data, ref Remote);    Console.WriteLine(Encoding.ASCII.GetString(data, 0, recv));    newsock.SendTo(data, recv, SocketFlags.None, Remote);  }}

void MainInfo(){  byte[] data = new byte[1024];//定義一個數組用來做數據的緩沖區  string input, stringData;  IPEndPoint ipep = new IPEndPoint(IPAddress.Parse("192.168.1.21"), 9050);  Socket server = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);  string welcome = "Hello,are you there?";  data = Encoding.ASCII.GetBytes(welcome);  server.SendTo(data, data.Length, SocketFlags.None, ipep);//將數據發送到指定的終結點  IPEndPoint sender = new IPEndPoint(IPAddress.Any, 0);  EndPoint Remote = (EndPoint)sender;  data = new byte[1024];  int recv = server.ReceiveFrom(data, ref Remote);//接受來自服務器的數據  Console.WriteLine("Message received from{0}:", Remote.ToString());  Console.WriteLine(Encoding.ASCII.GetString(data, 0, recv));  while (true)//讀取數據  {    input = richTextBox1.Text;//從鍵盤讀取數據    if (input == "text")//結束標記    {      break;    }    server.SendTo(Encoding.ASCII.GetBytes(input), Remote);//將數據發送到指定的終結點Remote    data = new byte[1024];    recv = server.ReceiveFrom(data, ref Remote);//從Remote接受數據    stringData = Encoding.ASCII.GetString(data, 0, recv);    Console.WriteLine(stringData);  }  Console.WriteLine("Stopping client");  server.Close();}

Socket serverSocket = null;Thread clientThread = null;Socket clientSocket = null;Thread thread = null;IPAddress ips = null;PEndPoint ipep = null;void ServerStart(){  ips = Dns.GetHostAddresses(Dns.GetHostName())[0];  //創建IPEndPoint實例    ipep = new IPEndPoint(ips, 9050);  //創建一個套接字    serverSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);  serverSocket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReuseAddress, true);  //將所創建的套接字與IPEndPoint綁定    serverSocket.Bind(ipep);  //設置套接字為收聽模式    serverSocket.Listen(20);  while (listenalive)  {    try    {      //在套接字上接收接入的連接        clientSocket = serverSocket.Accept();      clientThread = new Thread(new ParameterizedThreadStart(ReceiveData));      clientThread.Start(clientSocket);    }    catch (Exception ex)    {      WriteErrorLog(ex.Message);      serverSocket.Close();      serverSocket = null;    }  }}static void ReceiveData(object obj){  bool keepalive = true;  Socket s = obj as Socket;  Byte[] buffer = new Byte[1024];  //根據收聽到的客戶端套接字向客戶端發送信息    IPEndPoint clientep = (IPEndPoint)s.RemoteEndPoint;  Console.WriteLine("客戶端ip:" + clientep.Address + " 端口:" + clientep.Port);  string welcome = "連接服務器成功";  buffer = System.Text.Encoding.Unicode.GetBytes(welcome);  //向客戶端發送“連接服務器成功”消息  s.Send(buffer, buffer.Length, SocketFlags.None);  buffer = new Byte[1024];  int bufLen = 0;  string content = string.Empty;  while (true)  {    //在套接字上接收客戶端發送的信息      bufLen = 0;    try    {      bufLen = s.Receive(buffer);      if (bufLen == 0)      {        break;      }      content += System.Text.Encoding.Unicode.GetString(buffer, 0, bufLen);    }    catch (Exception ex)    {      break; ;    }  }  Send(s, content);  s = null;  buffer = null;  clientep = null;  Thread.CurrentThread.Abort();}

void Send(string content){  byte[] data = new byte[1024];  newclient = new System.Net.Sockets.Socket(System.Net.Sockets.AddressFamily.InterNetwork, System.Net.Sockets.SocketType.Stream, System.Net.Sockets.ProtocolType.Tcp);  ie = new System.Net.IPEndPoint(System.Net.IPAddress.Parse(ipadd), port);//服務器的IP和端口  try  {    //因為客戶端只是用來向特定的服務器發送信息，所以不需要綁定本機的IP和端口。不需要監聽。    newclient.Connect(ie);  }  catch (System.Net.Sockets.SocketException e)  {    Console.WriteLine(e.ToString());    return;  }  int recv = newclient.Receive(data);  //連接服務器成功  string stringdata = System.Text.Encoding.Unicode.GetString(data, 0, recv);  if (stringdata == "連接服務器成功")  {    newclient.Send(System.Text.Encoding.Unicode.GetBytes(content));    newclient.Shutdown(System.Net.Sockets.SocketShutdown.Send);    data = new byte[1024];    recv = newclient.Receive(data);    string result = System.Text.Encoding.Unicode.GetString(data, 0, recv);         newclient.Shutdown(System.Net.Sockets.SocketShutdown.Receive);    newclient.Close();    MessageBox.Show(result);  }  else  {    MessageBox.Show("連接服務器失敗", "友情提示");  }}