覆盖MFC / Visual C ++中的OnCancel按钮

Question

I have a model dialog. I overrided OnCancel function to stop unexpected exiting by pressing ESC button. But this caused a new problem. I can't close the application by using close (x) button. My implementation of function is:

void MyDlg::OnCancel()
{
}

Answer 1

Closing a dialog effectively cancels it. Since you have disabled close in your OnCancel handler, then nothing will happen.

To disable ESC only, you need to preprocess the keyboard messages:

BOOL CYourDlg::PreTranslateMessage(MSG* pMsg)
{
   switch ( pMsg->message )
   {
       case WM_KEYDOWN:

           switch( pMsg->wParam )
           {
               case VK_ESCAPE:
               case VK_CANCEL: return true;
           }
           break;
   }

   return CDialog::PreTranslateMessage(pMsg);
}