花开花落，我心依旧

class MessageBoxTimeOut
    {
        private string _caption;
 
        public void Show(string text, string caption, int timeout)
        {
            this._caption = caption;
            StartTimer(timeout);
            MessageBox.Show(text, caption);
        }
 
        private void StartTimer(int interval)
        {
            Timer timer = new Timer();
            timer.Interval = interval;
            timer.Tick += new EventHandler(Timer_Tick);
            timer.Enabled = true;
        }
 
        private void Timer_Tick(object sender, EventArgs e)
        {
            KillMessageBox();
            //停止计时器
            ((Timer)sender).Enabled = false;
        }
 
        [DllImport("coredll.dll", EntryPoint = "FindWindow", 
                                       CharSet = CharSet.Auto)]
        private extern static IntPtr FindWindow
                  (string lpClassName, string lpWindowName);
 
        [DllImport("coredll.dll", CharSet = CharSet.Auto)]
        public static extern int PostMessage(IntPtr hWnd, int msg, 
                                             IntPtr wParam, IntPtr lParam);
 
        public const int WM_CLOSE = 0x10;
 
        private void KillMessageBox()
        {
            //查找MessageBox的弹出窗口,注意对应标题
            IntPtr ptr = FindWindow(null, this._caption);
            if (ptr != IntPtr.Zero)
            {
                //查找到窗口则关闭
                PostMessage(ptr, WM_CLOSE, IntPtr.Zero, IntPtr.Zero);
            }
        }
    }