程序控制开始菜单的弹出

基本思路为，寻找开始菜单按钮窗口，并模拟用户单击 

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;
   }