程序控制开始菜单的弹出 C#

void pop()
  {
User32.EnumWindows(new EnumProc(Enum), 0);
  }
  private bool Enum(IntPtr hWnd, uint param)
  {
User32.STRINGBUFFER buffer=new User32.STRINGBUFFER();
User32.GetClassName(hWnd, ref buffer, 256);
if (buffer.szText == "Shell_TrayWnd")
{
 User32.EnumChildWindows(hWnd, new EnumProc(Enum2), 0);
 return false;
}
else return true;
  }
  IntPtr lastForeGroundWindow;
  private bool Enum2(IntPtr hWnd, uint param)
  {
User32.STRINGBUFFER buffer = new User32.STRINGBUFFER();
User32.GetClassName(hWnd, ref buffer, 256);
if (buffer.szText == "Button")
{
 if (User32.SendMessage(hWnd, WndMsg.BM_GETSTATE, 0, 0) == User32.BST_PUSHED)
 {
  User32.SetForegroundWindow(lastForeGroundWindow);
 }
 else
 {
  lastForeGroundWindow = User32.GetForegroundWindow();
  User32.SetForegroundWindow(hWnd);
  User32.PostMessage(hWnd, WndMsg.BM_CLICK, 0, 0);
 }
 return true;
}
else
 return false;
  }