CWnd::IsDialogMessage
This method determines whether the specified message is intended for a modeless dialog box. If it is, this method processes the message. When the IsDialogMessage function processes a message, it checks for keyboard messages and converts them to selection commands for the corresponding dialog box. For example, the TAB key selects the next control or group of controls, and the DOWN ARROW key selects the next control in a group.
You must not pass a message processed by IsDialogMessage to the TranslateMessage or DispatchMessage Windows CE functions, because it has already been processed.
BOOL IsDialogMessage(
LPMSG lpMsg );
Parameters
lpMsg
Points to an MSG structure that contains the message to be checked.
Return Value
Specifies whether the method has processed the given message. It is nonzero if the message has been processed; otherwise, it is zero. If the return is 0, call the CWnd::PreTranslateMessage method of the base class to process the message. In an override of the CWnd::PreTranslateMessage method the code looks like this :