20041206: WHEN SHOULD NOT WE CALL THE BASE CLASS'S CORRESPONDING FUNCTION?
void CDropDownBotton :: OnKeyDown (UINT nChar, UINT nRepCnt, UINT nFlags) {// TODO: Add your message handler code here and / or call default if (nChar == VK_RETURN || nChar == VK_ESCAPE) {if (m_pOrigParent-> Isdropdowndialogdown ()) m_porigparent-> onDropdownButton ();} // cbutton :: onkeydown (nchar, nrepcnt, nflags);}
in the code snippet above, the base class's corresponding function CButton :: OnKeyDown (nChar, nRepCnt, nFlags); is comment out.The reason is that the CButton has already been destroyed before we call CButton :: OnKeyDown.
Another Way To Fix This Kind of bug is to call cwnd :: postmeassage () instead of calling method to design.
