The container control sends a WM_CONTROL (in Container Controls) message with the CN_DRAGAFTER notification code to its owner whenever the container receives a DM_DRAGOVER message. The CN_DRAGAFTER notification code is sent only if the CA_ORDEREDTARGETEMPHASIS or CA_MIXEDTARGETEMPHASIS attribute of the CNRINFO data structure is set and the current view is the name, text, or details view.
param1 USHORT id /* Container control ID. */ USHORT CN_DRAGAFTER /* Notification code. */ param2 PCNRDRAGINFO pCnrDragInfo /* Pointer to a CNRDRAGINFO structure. */ returns USHORT usDrop /* Drop indicator. */ USHORT usDefaultOp /* Default operation. */