DragAcceptFiles

DragAcceptFiles is an API function in the Microsoft Windows operating system that allows a window to receive drag-and-drop file transfer operations. The function prototype is declared in the shellapi.h header as follows:

DragAcceptFiles(HWND hWnd, BOOL fAccept)

The first parameter, hWnd, specifies the handle of the window that will receive the drag‑and‑drop file data. The second parameter, fAccept, is a Boolean value that determines whether the window will accept or reject file drops. Passing TRUE enables file drop handling for the specified window; passing FALSE disables it.

When enabled, the window must process the WM_DROPFILES message that the system sends once a drop operation is completed. The Win32 API DragQueryFile can then be used to enumerate the file names that were dropped, and DragFinish is called to release the memory allocated for the drop data. This mechanism is commonly used by file‑manager applications, editors, and other tools that allow users to drag files onto the application's window for opening or importing.

Because DragAcceptFiles is a legacy component of the Shell API, newer drag‑and‑drop APIs such as IDropTarget in COM are recommended for modern applications, but DragAcceptFiles remains available for compatibility and simplicity in many existing programs.