//客户端
 1 using System;
  2 using System.Collections.Generic;
  3 using System.ComponentModel;
  4 using System.Data;
  5 using System.Drawing;
  6 using System.Text;
  7 using System.Windows.Forms;
  8 
  9 using System.Net;
 10 using System.Net.Sockets;
 11 
 12 namespace Client
 13 {
 14     public partial class ClientMain : Form
 15     {
 16         public ClientMain()
 17         {
 18             InitializeComponent();
 19         }
 20 
 21         private IPEndPoint ServerInfo;
 22         private Socket ClientSocket;
 23         private Byte[] MsgBuffer;
 24         private Byte[] MsgSend;
 25 
 26         private void ClientMain_Load(object sender, EventArgs e)
 27         {
 28             this.CmdSend.Enabled = false;
 29             this.CmdExit.Enabled = false;
 30 
 31             ClientSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
 32             MsgBuffer = new Byte[65535];
 33             MsgSend = new Byte[65535];
 34             CheckForIllegalCrossThreadCalls = false;
 35 
 36             Random TRand=new Random();
 37             this.UserName.Text = "用户" + TRand.Next(10000).ToString();
 38         }
 39 
 40         private void CmdEnter_Click(object sender, EventArgs e)
 41         {
 42             ServerInfo = new IPEndPoint(IPAddress.Parse(this.ServerIP.Text), Convert.ToInt32(this.ServerPort.Text));
 43 
 44             try
 45             {
 46                 ClientSocket.Connect(ServerInfo);
 47 
 48                 ClientSocket.Send(Encoding.Unicode.GetBytes("用户： " + this.UserName.Text + " 进入系统！\n"));
 49 
 50                 ClientSocket.BeginReceive(MsgBuffer, 0, MsgBuffer.Length, 0, new AsyncCallback(ReceiveCallBack), null);
 51 
 52                 this.SysMsg.Text += "登录服务器成功！\n";
 53                 this.CmdSend.Enabled = true;
 54                 this.CmdEnter.Enabled = false;
 55                 this.CmdExit.Enabled = true;
 56             }
 57             catch
 58             {
 59                 MessageBox.Show("登录服务器失败，请确认服务器是否正常工作！");
 60             }
 61         }
 62 
 63         private void ReceiveCallBack(IAsyncResult AR)
 64         {
 65             try
 66             {
 67                 int REnd = ClientSocket.EndReceive(AR);
 68                 this.RecieveMsg.AppendText(Encoding.Unicode.GetString(MsgBuffer, 0, REnd));
 69                 ClientSocket.BeginReceive(MsgBuffer, 0, MsgBuffer.Length, 0, new AsyncCallback(ReceiveCallBack), null);
 70 
 71             }
 72             catch
 73             {
 74                 MessageBox.Show("已经与服务器断开连接！");
 75                 this.Close();
 76             }
 77 
 78         }
 79 
 80         private void CmdSend_Click(object sender, EventArgs e)
 81         {
 82             MsgSend = Encoding.Unicode.GetBytes(this.UserName.Text + "说：\n" + this.SendMsg.Text + "\n");
 83             if (ClientSocket.Connected)
 84             {
 85                 ClientSocket.Send(MsgSend);
 86