CMemDC::IsMemDC
Indicates whether the device context that GetDC returns is a memory device context.
BOOL IsMemDC() const;
Return Value
TRUE if a memory device context is being used for drawing operations; otherwise FALSE.
Remarks
If IsMemDC returns TRUE, CMemDC::GetDC returns a memory device context (DC). If IsMemDC returns FALSE, GetDC returns the screen DC that was originally passed in the constructor.
A return value of FALSE means that the CMemDC could not be initialized to support offscreen drawing.
Requirements
Header: afxglobals.h