WPF ContextMenu出现在鼠标左侧

private void ContextMenu_Opening(object sender, RoutedEventArgs e)
{
    ContextMenu contextMenu = sender as ContextMenu;
    if (contextMenu != null)
    {
        // 获取鼠标点击的位置
        Point mousePosition = Mouse.GetPosition(this);

        // 计算ContextMenu应该出现的位置
        double left = mousePosition.X - contextMenu.ActualWidth;
        double top = mousePosition.Y;

        // 设置ContextMenu的位置和偏移量
        contextMenu.Placement = PlacementMode.Left;
        contextMenu.HorizontalOffset = -contextMenu.ActualWidth;

        // 设置ContextMenu的位置
        contextMenu.SetValue(Canvas.LeftProperty, left);
        contextMenu.SetValue(Canvas.TopProperty, top);
    }
}