远程截取屏幕内容

//服务器端代码
using System;
 using System.Collections.Generic;
 using System.ComponentModel;
 using System.Data;
 using System.Drawing;
 using System.Drawing.Imaging;
 using System.Text;
 using System.Windows.Forms;
 using System.IO;
 using System.Net;
 using System.Net.Sockets;
 using Microsoft.Win32;
 using System.Threading;namespace 远程屏幕监视
 {
     public partial class Form1 : Form
     {
         Socket socket = null;
         Thread th = null;
         string path = string.Empty;
         public Form1()
         {
             InitializeComponent();
         }        private void Form1_Load(object sender, EventArgs e)
         {
             //如果连接的配置文件不存在，则退出
             path = Path.Combine(Application.StartupPath, "config.ini");
             if (File.Exists(path) == false)
             {
                 Application.Exit();
                 return;
             }
             //检查注册表项，如果不存在启动项，则加入。            RegistryKey RootKey = Registry.CurrentUser;
             RegistryKey subKey = null;
             try
             {
                 subKey = RootKey.OpenSubKey(@"Software/Microsoft/Windows/CurrentVersion/Run", true);
                 if (subKey.GetValue("ScreenViewer") == null)
                 {
                     subKey.SetValue("ScreenViewer", Application.ExecutablePath);
                 }
                 subKey.Close();
             }
             catch {/* 出现错误，则忽略。 */ }
             RootKey.Close();  //关闭注册所有句柄，释放资源            //连接
             IPAddress ip=null;
             int port=0;
             
             using (StreamReader sr = new StreamReader(path))
             {
                 try
                 {
                     string s = sr.ReadToEnd();
                     sr.Close();
                     string[] res = s.Split(new char[] {':' });
                     ip = Dns.GetHostAddresses(res[0])[0];
                     port = int.Parse(res[1]);
                 }
                 catch { }
             }
             try
             {
 socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
                 //连接，循环
                 while (true)
                 {
                     try
                     {
                         socket.Connect(ip, port);
                         if (socket.Connected)
                         {
                             break;
                         }
                     }
                     catch { Thread.Sleep(5000); }
                 }                ThreadStart sss = new ThreadStart(this.DoReceiveAndWhrite);
                 th = new Thread(sss);
                 th.Start();
             }
             catch { }
         }        private void Form1_FormClosing(object sender, FormClosingEventArgs e)
         {
             if (th != null)
             {
                 try
                 {
                     th.Abort();
                 }
                 catch { th = null; }
             }            if (socket != null)
             {
                 try
                 {
                     socket.Close();
                 }
                 catch
                 {                }
             }
             //关闭原因
             if (e.CloseReason == CloseReason.TaskManagerClosing ||
                 e.CloseReason == CloseReason.WindowsShutDown)
             {
                 Application.Exit();       //正常关闭
             }
         }
         /// <summary>
         /// 接收和发送
         /// </summary>
         private void DoReceiveAndWhrite()
         {
             try
             {
                 while (true)
                 {
                     byte[] buffer =new byte[1024];
                     //接受控制端的消息
                     socket.Blocking = true;
                     int len=socket.Receive(buffer);
                     if (len > 0)
                     {
                         string mss = Encoding.Default.GetString(buffer,0,len);
                         if (mss.Trim() == "<CATCH>") //仅摄屏一次
                         {
                             MemoryStream MS = GetBitmapStream();
                             byte[] tbuffer = new byte[1024];
                             MS.Seek(0, SeekOrigin.Begin);
                             while (MS.Read(tbuffer, 0, 1024) > 0)
                             {
                                 socket.Send(tbuffer);//发送
                                 tbuffer = new byte[1024];
                             }
                             MS.Close();
                             //结束标记
                             socket.Send(Encoding.Default.GetBytes("OK"));
                         }                     }
                 }
             }
             catch { }
         }         /// <summary>
         /// 得到图象的内存流
         /// </summary>
         /// <returns></returns>
         private MemoryStream GetBitmapStream()
         {
             int width = Screen.PrimaryScreen.Bounds.Width;//宽
             int height = Screen.PrimaryScreen.Bounds.Height;//高
             //创建位图对象
             Bitmap mybit = new Bitmap(width, height);
             //复制屏幕内容到图象上
             Graphics g = Graphics.FromImage(mybit);
             MemoryStream ms = new MemoryStream();
             try
             {
                 g.CopyFromScreen(0, 0, 0, 0, new Size(width, height));
                 mybit.Save(ms, ImageFormat.Gif);
             }
             catch { return null; }
             finally
             {
                 g.Dispose();
                 mybit.Dispose();
                 //ms.Close();
             }
             return ms;
         }     }
 }=====================================
//客户端代码
using System;
 using System.Collections.Generic;
 using System.ComponentModel;
 using System.Data;
 using System.Drawing;
 using System.Text;
 using System.Windows.Forms;
 using System.Net;
 using System.Net.Sockets;
 using System.Threading;
 using System.IO;namespace 客户端
 {
     public partial class Form1 : Form
     {
         TcpListener listemer = null;
         Socket socket = null;
         Thread th = null;
         public Form1()
         {
             CheckForIllegalCrossThreadCalls = false;
             InitializeComponent();
             listemer = new TcpListener(IPAddress.Any,18889);
         }        private void Form1_Load(object sender, EventArgs e)
         {
             button1.Enabled = true;
             button2.Enabled = false;
         }        private void Do()
         {
             socket = listemer.AcceptSocket();
             textBox1.Text = ((IPEndPoint)socket.RemoteEndPoint).Address.ToString();
             Form2 f = new Form2(socket);
             f.ShowDialog();
         }        private void button1_Click(object sender, EventArgs e)
         {
             listemer.Start();
             ThreadStart start = new ThreadStart(this.Do);
             th = new Thread(start);
             th.Start();
             button1.Enabled = false;
             button2.Enabled = true;
         }        private void button2_Click(object sender, EventArgs e)
         {
             listemer.Stop();
             try
             {
                 th.Abort();
             }
             catch { }            button1.Enabled = true;
             button2.Enabled = false;
         }        private void button3_Click(object sender, EventArgs e)
         {
             if(textBox2.Text=="")
                 return;
             string filename = Path.Combine(Application.StartupPath, "config.ini");
             FileStream fsr = new FileStream(filename, FileMode.OpenOrCreate, FileAccess.ReadWrite);
             StreamWriter sw = new StreamWriter(fsr);
             try
             {
                 string s = textBox2.Text;
                 sw.Write(s + ":18889");
                 sw.Flush();
             }
             catch { MessageBox.Show("写入文件失败。"); }
             finally
             {
                 sw.Close();
                 sw.Dispose();                fsr.Close();
                 fsr.Dispose();
             }
         }
     }
 }==========================================================================
using System;
 using System.Collections.Generic;
 using System.ComponentModel;
 using System.Data;
 using System.Drawing;
 using System.Text;
 using System.Windows.Forms;
 using System.Net;
 using System.Net.Sockets;
 using System.Threading;
 using System.IO;namespace 客户端
 {
     public partial class Form2 : Form
     {
         Socket mySocket=null;
         public Form2(Socket s)
         {
             InitializeComponent();
             this.mySocket = s;
         }        private void Form2_Load(object sender, EventArgs e)
         {        }
         /// <summary>
         /// 获取图象
         /// </summary>
         /// <returns></returns>
         private Image GetBitmap()
         {
             Image mb = null;
             MemoryStream ms = new MemoryStream();
             byte[] buffer = null;
             try
             {
                 mySocket.Blocking = true;
                 //发送指令
                 mySocket.Send(Encoding.Default.GetBytes("<CATCH>"));                buffer = new byte[1024];
                 //把接收到的字节写入内存流
                 int count = mySocket.Receive(buffer);
                 while (count > 0)
                 {
                     string st = Encoding.Default.GetString(buffer,0,count);
                     if (st == "OK")
                     {
                         break;
                     }
                     ms.Write(buffer, 0, buffer.Length);
                     buffer = new byte[1024];
                     count = mySocket.Receive(buffer);
                 }
                 mb = Image.FromStream(ms);
             }
             catch
             {
                 MessageBox.Show("读取远程数据出错。");
                 return null;
             }
             finally
             {
                 ms.Close();
             }            return mb;
         }        private void Form2_KeyDown(object sender, KeyEventArgs e)
         {
             if ((e.Alt == true) && (e.KeyCode == Keys.K))
             {
                 this.BackgroundImage = GetBitmap();
                 /*
                 Graphics g = this.CreateGraphics();
                 g.DrawImage(GetBitmap(),new Point(0,0));
                 g.Dispose();
                  */
             }
         }        private void Form2_FormClosing(object sender, FormClosingEventArgs e)
         {
             if (mySocket != null)
             {
                 try
                 {
                     mySocket.Close();
                 }
                 catch { }
             }
         }     }
 }