wpf中的BringToFront

public static class FrameworkElementExt
  {
    public static void BringToFront(this FrameworkElement element)
    {
      if (element == null) return;

      Panel parent = element.Parent as Panel;
      if (parent == null) return;

      var maxZ = parent.Children.OfType<UIElement>()
        .Where(x => x != element)
        .Select(x => Panel.GetZIndex(x))
        .Max();
      Panel.SetZIndex(element, maxZ + 1);
    }
  }