IVsObjectList::QueryDragDrop Method (UInt32, IDataObject^, UInt32, UInt32)

Visual Studio 2015

Returns a flag indicating whether the given list item supports a drag-and-drop operation.

Namespace: Microsoft.VisualStudio.Shell.Interop
Assembly: Microsoft.VisualStudio.Shell.Interop (in Microsoft.VisualStudio.Shell.Interop.dll)

Syntax

C++

int QueryDragDrop(
	unsigned int index,
	IDataObject^ pDataObject,
	unsigned int grfKeyState,
	unsigned int% pdwEffect
)

Parameters

index: Type: System::UInt32
[in] Specifies the index of the list item of interest.

pDataObject: Type: Microsoft.VisualStudio.OLE.Interop::IDataObject^
[in] Pointer to an IDataObject being dropped.

grfKeyState: Type: System::UInt32
[in] Current state of the keyboard and the mouse modifier keys.

pdwEffect: Type: System::UInt32
[in, out] On input, the effect being requested. On output, the effect that your object list allows.

Return Value

Type: System::Int32

If the method succeeds, it returns S_OK. If it fails, it returns an error code.

Remarks

COM Signature

From vsshell.idl:

C++

HRESULT IVsObjectList::QueryDragDrop(
   [in] ULONG Index,
   [in] IDataObject *pDataObject,
   [in] DWORD grfKeyState,
   [in, out]DWORD * pdwEffect
);

When the user drags an item and hovers over your item in Class View, the environment calls QueryDragDrop to see if a drag-drop operation is supported.

This method is very similar to the standard COM DragOver method. Values for grfKeyState can be a bitwise "or" combination of any number of the following: MK_CONTROL, MK_SHIFT, MK_ALT, MK_LBUTTON, MK_MBUTTON, and MK_RBUTTON. Values for the pdwEffect are taken from the DROPEFFECT enumeration.