IDropSource::QueryContinueDrag  6J_4G2

Determines whether a drag-and-drop operation should be continued, canceled, or completed. You do not call this method directly. The OLE DoDragDrop3YY1_Q5 function calls this method during a drag-and-drop operation.

HRESULT QueryContinueDrag(

Parameters

fEscapePressed

[in] Specifies whether the Esc key has been pressed since the previous call to IDropSource::QueryContinueDrag or to DoDragDrop3YY1_Q5 if this is the first call to QueryContinueDrag. A TRUE value indicates the end user has pressed the escape key; a FALSE value indicates it has not been pressed.

grfKeyState

[in] Current state of the keyboard modifier keys on the keyboard. Valid values can be a combination of any of the flags MK_CONTROL, MK_SHIFT, MK_ALT, MK_BUTTON, MK_LBUTTON, MK_MBUTTON, and MK_RBUTTON.

Return Values

This method supports the standard return values E_UNEXPECTED and E_OUTOFMEMORY, as well as the following:

S_OK

The drag operation should continue. This result occurs if no errors are detected, the mouse button starting the drag-and-drop operation has not been released, and the Esc key has not been detected.

DRAGDROP_S_DROP

The drop operation should occur completing the drag operation. This result occurs if grfKeyState indicates that the key that started the drag-and-drop operation has been released.

DRAGDROP_S_CANCEL

The drag operation should be canceled with no drop operation occurring. This result occurs if fEscapePressed is TRUE, indicating the Esc key has been pressed.

Remarks

The DoDragDrop3YY1_Q5 function calls IDropSource::QueryContinueDrag whenever it detects a change in the keyboard or mouse button state during a drag-and-drop operation. IDropSource::QueryContinueDrag must determine whether the drag-and-drop operation should be continued, canceled, or completed based on the contents of the parameters grfKeyState and fEscapePressed.

See Also