SENDMessage(tmph,WM_SYSKEYDOWN,VK_control,0);

  SENDMessage(tmph,WM_SYSKEYDOWN,ord('A'),0);

  Sleep(800);

  SENDMessage(tmph,WM_SYSKEYUP,ORD('A'),0);

  SENDMessage(tmph,WM_SYSKEYUP,VK_CONTROL,0);

手工在窗体上按ctrl+a是有反应,可是为什么用这个组合键不行呢?