int _DragEvent(int event_, byte[] b)
{
if (!_isDragMode)
{
return(0);
}
DDEvent ev = (DDEvent)event_;
if (ev == DDEvent.Leave)
{
if (!_wTargetControl.Is0)
{
_InvokeDT(_wTargetControl, ev, 0, 0, default);
_wTargetControl = default;
}
return(0);
}
var a = Serializer_.Deserialize(b);
int effect = a[0], keyState = a[1]; POINT pt = new(a[2], a[3]);
if (ev == DDEvent.Enter)
{
_data = new System.Windows.DataObject();
var t = new DDData {
files = a[4], shell = a[5], text = a[6], linkName = a[7]
};
if (t.files != null)
{
_data.SetData("FileDrop", t.files);
}
if (t.shell != null)
{
_SetDataBytes("Shell IDList Array", t.shell);
}
if (t.text != null)
{
_data.SetData("UnicodeText", t.text);
}
if (t.linkName != null)
{
_SetDataBytes("FileGroupDescriptorW", t.linkName);
}
//workaround for: SetData writes byte[] in wrong format, probably serialized
void _SetDataBytes(string name, byte[] a) => _data.SetData(name, new MemoryStream(a), false);
}
int ef = 0;
var w = _wWindow.ChildFromXY(pt, WXYCFlags.ScreenXY);
if (w.Is0)
{
w = _wWindow;
}
if (w != _wTargetControl && !_wTargetControl.Is0)
{
_InvokeDT(_wTargetControl, DDEvent.Leave, 0, 0, default);
_wTargetControl = default;
}
if (!w.Is0 && w.IsOfThisProcess && w.IsEnabled(true))
{
if (ev != 0 && _wTargetControl.Is0)
{
if (ev == DDEvent.Over)
{
ev = 0;
}
else
{
_InvokeDT(w, DDEvent.Enter, effect, keyState, pt);
}
}
ef = _InvokeDT(_wTargetControl = w, ev, effect, keyState, pt);
}
if (ev == DDEvent.Drop)
{
_wTargetControl = default;
}
int _InvokeDT(wnd w, DDEvent ev, int effect, int keyState, POINT pt)
{
if (w.IsOfThisThread)
{
return(_InvokeDropTarget(w, ev, effect, keyState, pt));
}
var d = HwndSource.FromHwnd(w.Window.Handle)?.Dispatcher;
return(d?.Invoke(() => _InvokeDropTarget(w, ev, effect, keyState, pt)) ?? 0);
}
return(ef);
}
