vc 模拟按win+D键（最小化所有窗口）

keybd_event(VK_LWIN, 0, 0 ,0);/
 keybd_event('D', 0, 0 ,0);
 keybd_event('D', 0, KEYEVENTF_KEYUP ,0);
 keybd_event(VK_LWIN, 0, KEYEVENTF_KEYUP,0);