The WM_DROPFILES message is sent when the user releases the left mouse button while the cursor is in the window of an application that has registered itself as a recipient of dropped files.
WM_DROPFILES
hDrop = (HANDLE) wParam; // handle of internal drop structure
Parameters
hDrop
Value of wParam. Identifies an internal structure describing the dropped files. This handle is used by the DragFinish, DragQueryFile, and DragQueryPoint functions to retrieve information about the dropped files.
Return Values
An application should return zero if it processes this message.
See Also