using System; 
using System.Collections.Generic; 
using System.ComponentModel; 
using System.Data; 
using System.Drawing; 
using System.Text; 
using System.Windows.Forms; 
using System.Runtime.InteropServices; 
namespace WindowsApplication1 
{ 
 public partial class AutoDeleteMessageBox : Form 
 { 
  [DllImport("user32.dll", EntryPoint = "FindWindow", CharSet = CharSet.Auto)] 
  private extern static IntPtr FindWindow(string lpClassName, string lpWindowName); 
  [DllImport("user32.dll", CharSet = CharSet.Auto)] 
  public static extern int PostMessage(IntPtr hWnd, int msg, IntPtr wParam, IntPtr lParam); 
  public const int WM_CLOSE = 0x10; 
  public AutoDeleteMessageBox() 
  { 
   InitializeComponent(); 
  } 
  private void button1_Click(object sender, EventArgs e) 
  { 
   StartKiller(); 
   MessageBox.Show("3秒钟后自动关闭MessageBox窗口", "MessageBox"); 
  } 
  private void StartKiller() 
  { 
   Timer timer = new Timer(); 
   timer.Interval = 3000; //3秒启动 
   timer.Tick += new EventHandler(Timer_Tick); 
   timer.Start(); 
  } 
  private void Timer_Tick(object sender, EventArgs e) 
  { 
   KillMessageBox(); 
   //停止Timer 
   ((Timer)sender).Stop(); 
  } 
  private void KillMessageBox() 
  { 
   //按照MessageBox的标题，找到MessageBox的窗口 
   IntPtr ptr = FindWindow(null, "MessageBox"); 
   if (ptr != IntPtr.Zero) 
   { 
    //找到则关闭MessageBox窗口 
    PostMessage(ptr, WM_CLOSE, IntPtr.Zero, IntPtr.Zero); 
   } 
  } 
 } 
}