silverlight 获取控件间的相对位置

1）前台代码

<UserControl x:Class="SilverlightApplication9.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d"
    d:DesignHeight="300" d:DesignWidth="400">


    <Grid x:Name="LayoutRoot" Background="White">
        <Grid.RowDeFinitions>
            <RowDeFinition Height="50"></RowDeFinition>
            <RowDeFinition Height="*"></RowDeFinition>
        </Grid.RowDeFinitions>
        <Button Name="TestButton" Width="200" Height="24" Content="Add" Grid.Row="0"></Button>
        <ScrollViewer Name="TestScrollViewer" Grid.Row="1">
            <StackPanel Name="TestStackPanel" Orientation="Vertical">
            </StackPanel>
        </ScrollViewer>
    </Grid>
</UserControl>

2）后台代码

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;


namespace SilverlightApplication9
{
    public partial class MainPage : UserControl
    {
        private int counter = 1;
        public MainPage()
        {
            InitializeComponent();
            TestButton.Click += new RoutedEventHandler(TestButton_Click);
        }
        void TestButton_Click(object sender,RoutedEventArgs e)
        {
            //新添加Button
            Button button = new Button();
            button.Width = 200;
            button.Height = 100;
            button.Content = counter++;
            button.Click += new RoutedEventHandler(button_Click);
            TestStackPanel.Children.Add(button);
        }


        void button_Click(object sender,RoutedEventArgs e)
        {
            Button button = sender as Button;
            //获取Button控件相对于StackPanel的位置
            GeneralTransform gt = button.TransformToVisual(TestStackPanel);
            Point point = gt.Transform(new Point(0,0));
            button.Content = "(" + point.X + "," + point.Y + ")";
        }
    }
}