CMDIChildWnd* MDIGetActive( BOOL* pbMaximized = NULL ) const;
pbMaximized
Set to TRUE on return if the window is maximized; otherwise FALSE.
Retrieves the current active MDI child window, along with a flag indicating whether the child window is maximized.
A pointer to the active MDI child window.
CMDIFrameWnd::MDIActivate, WM_MDIGETACTIVE