Hi there:

 

I met with one problem. I try to send a simulated keystroke to another application (such as Notepad) to invoke one of its functions, but when I minimize the window of "Notepad", the message cannot be received even I used the SetFocus() and SetActiveWindow() function. When it is maximized, it works. Anyone can help? Here are my codes:

 

int main( )
{
  HWND hwnd = FindWindow(NULL, "Untitled - Notepad");
  short f3_key = VK_F3;
  UINT scancode = MapVirtualKey(f3_key, 0);

 

  if (hwnd!=NULL){
       printf("Notepad is running!\n");
       SetActiveWindow(hwnd);
       SetFocus(hwnd);
  }

  PostMessage(hwnd, WM_SYSKEYDOWN, f3_key, scancode);
  PostMessage(hwnd, WM_SYSCHAR, f3_key, scancode);
  PostMessage(hwnd, WM_SYSKEYUP, f3_key, scancode);

  

return 0;
}