HBITMAP hbmResult = :CreateCompatibleBit地图(CClientDC(NULL), w, h);//这句话什么意思

HBITMAP hbmResult = ::CreateCompatibleBitmap(CClientDC(NULL), w, h);//这句话什么意思?
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
------解决方案--------------------
CreateCompatibleBitmap就是创建兼容DC
CClientDC(NULL)是基于CDC的类,获取窗口客户区的DC
相当于GetDC(0)