public HRESULT QueryAcceptData(IComDataObject lpdataobj, IntPtr lpcfFormat, RECO reco, BOOL fReally, IntPtr hMetaPict)
{
Debug.WriteLineIf(RichTextDbg.TraceVerbose, "IRichEditOleCallback::QueryAcceptData(reco=" + reco + ")");
if (reco == RECO.DROP)
{
if (owner.AllowDrop || owner.EnableAutoDragDrop)
{
MouseButtons b = Control.MouseButtons;
Keys k = Control.ModifierKeys;
User32.MK keyState = 0;
// Due to the order in which we get called, we have to set up the keystate here.
// First GetDragDropEffect is called with grfKeyState == 0, and then
// QueryAcceptData is called. Since this is the time we want to fire
// OnDragEnter, but we have yet to get the keystate, we set it up ourselves.
if ((b & MouseButtons.Left) == MouseButtons.Left)
{
keyState |= User32.MK.LBUTTON;
}
if ((b & MouseButtons.Right) == MouseButtons.Right)
{
keyState |= User32.MK.RBUTTON;
}
if ((b & MouseButtons.Middle) == MouseButtons.Middle)
{
keyState |= User32.MK.MBUTTON;
}
if ((k & Keys.Control) == Keys.Control)
{
keyState |= User32.MK.CONTROL;
}
if ((k & Keys.Shift) == Keys.Shift)
{
keyState |= User32.MK.SHIFT;
}
lastDataObject = new DataObject(lpdataobj);
if (!owner.EnableAutoDragDrop)
{
lastEffect = DragDropEffects.None;
}
var e = new DragEventArgs(lastDataObject,
(int)keyState,
Control.MousePosition.X,
Control.MousePosition.Y,
DragDropEffects.All,
lastEffect);
if (fReally == 0)
{
// we are just querying
// We can get here without GetDragDropEffects actually being called first.
// This happens when you drag/drop between two rtb's. Say you drag from rtb1 to rtb2.
// GetDragDropEffects will first be called for rtb1, then QueryAcceptData for rtb1 just
// like in the local drag case. Then you drag into rtb2. rtb2 will first be called in this method,
// and not GetDragDropEffects. Now lastEffect is initialized to None for rtb2, so we would not allow
// the drag. Thus we need to set the effect here as well.
e.Effect = ((keyState & User32.MK.CONTROL) == User32.MK.CONTROL) ? DragDropEffects.Copy : DragDropEffects.Move;
owner.OnDragEnter(e);
}
else
{
owner.OnDragDrop(e);
lastDataObject = null;
}
lastEffect = e.Effect;
if (e.Effect == DragDropEffects.None)
{
Debug.WriteLineIf(RichTextDbg.TraceVerbose, "\tCancel data");
return(HRESULT.E_FAIL);
}
else
{
Debug.WriteLineIf(RichTextDbg.TraceVerbose, "\tAccept data");
return(HRESULT.S_OK);
}
}
else
{
Debug.WriteLineIf(RichTextDbg.TraceVerbose, "\tCancel data, allowdrop == false");
lastDataObject = null;
return(HRESULT.E_FAIL);
}
}
else
{
return(HRESULT.E_NOTIMPL);
}
}
public HRESULT GetClipboardData(ref Richedit.CHARRANGE lpchrg, RECO reco, IntPtr lplpdataobj)
{
Debug.WriteLineIf(RichTextDbg.TraceVerbose, "IRichEditOleCallback::GetClipboardData");
return(HRESULT.E_NOTIMPL);
}