将框架元素从容器拖放到另一个容器

Question

我正在拖动项目以在WPF中制作FormBuilder。

我已经在画布上使用MouseLeftButtonDown和MouseMove事件实现了拖动。

我想使用MouseLeftButtonUp将项目移动到特定的StackPanel /画布中。

我需要在容器中获取此事件；我在目标Container上尝试过DragLeave和Drop，它们不会触发。

在MouseMove上，我总是将光标放在“拖动项”的中间，因此，在MouseUp上的目标容器上始终会有一个项。

如何将此项移至目标容器？

这是我的代码的某些部分：

    private void MainCanvas_MouseMove(object sender, MouseEventArgs e)
    {
        if (e.LeftButton == MouseButtonState.Pressed)
        {
            if (MovingObject != null)
            {
                Point P = e.GetPosition(MainCanvas);

                (MovingObject as FrameworkElement).SetValue(Canvas.LeftProperty, P.X - DeltaX);
                (MovingObject as FrameworkElement).SetValue(Canvas.TopProperty, P.Y - DeltaY);
            }
        }
    }

    private void Button_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
    {
        if (sender is Draggable)
        {
            var Sender = (Draggable)sender;
            PreviousParent = Sender.Parent as FrameworkElement;
            if (PreviousParent is StackPanel)
            {
                ((StackPanel)PreviousParent).Children.Remove(Sender);
                Point Point = e.GetPosition(MainCanvas);
                (Sender as FrameworkElement).SetValue(Canvas.LeftProperty, Point.X - Sender.ActualWidth/2);
                (Sender as FrameworkElement).SetValue(Canvas.TopProperty, Point.Y - Sender.ActualHeight / 2);
                MainCanvas.Children.Add(Sender);
            }
            MovingObject = Sender.ToDraggie();                
        }
        else
        {
            MovingObject = sender;
        }

        FirstXPos = e.GetPosition(sender as Control).X;
        FirstYPos = e.GetPosition(sender as Control).Y;

        DeltaX = ((Control)sender).ActualWidth / 2;
        DeltaY = ((Control)sender).ActualHeight / 2;
    }

    private void Button_MouseLeftButtonUp(object sender, MouseButtonEventArgs e)
    {
        MovingObject = null;
    }