Called in response to the WM_INITDIALOG message.
This message is sent to the dialog box during the Create, CreateIndirect, or DoModal calls, which occur immediately before the dialog box is displayed.
Override this member function if you need to perform special processing when the dialog box is initialized. In the overridden version, first call the base class OnInitDialog but disregard its return value. You will normally return TRUE from your overridden member function.
Windows calls the OnInitDialog function through the standard global dialog-box procedure common to all Microsoft Foundation Class Library dialog boxes, rather than through your message map, so you do not need a message-map entry for this member function.