SilverLight实现拖动代码

前台代码：

 

<UserControl
 xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
 xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
 x:Class="SilverlightApplication6.Page"
 Width="640" Height="480">

    <Canvas x:Name="LayoutRoot" Background="White">
        <Image Margin="263,185,249,167" Source="1.png" Stretch="Fill" MouseLeftButtonDown="Image_MouseLeftButtonDown"
       MouseMove="Image_MouseMove"
       MouseLeftButtonUp="Image_MouseLeftButtonUp"/>
    </Canvas>
</UserControl>

 

后台代码：

 

using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Ink;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;

namespace SilverlightApplication6
{
 public partial class Page : UserControl
 {
        bool trackingMouseMove = false;
        Point mousePosition;

  public Page()
  {
   // 需要初始化变量
   InitializeComponent();
  }

        private void Image_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
        {
            FrameworkElement element = sender as FrameworkElement;
            mousePosition = e.GetPosition(null);
            trackingMouseMove = true;
            if (null != element)
            {
                element.CaptureMouse();
                element.Cursor = Cursors.Hand;
            }

        }

        private void Image_MouseMove(object sender, MouseEventArgs e)
        {
            FrameworkElement element = sender as FrameworkElement;
            if (trackingMouseMove)
            {
                double deltaV = e.GetPosition(null).Y - mousePosition.Y;
                double deltaH = e.GetPosition(null).X - mousePosition.X;
                double newTop = deltaV + (double)element.GetValue(Canvas.TopProperty);
                double newLeft = deltaH + (double)element.GetValue(Canvas.LeftProperty);

                element.SetValue(Canvas.TopProperty, newTop);
                element.SetValue(Canvas.LeftProperty, newLeft);

                mousePosition = e.GetPosition(null);
            }

        }

        private void Image_MouseLeftButtonUp(object sender, MouseButtonEventArgs e)
        {
            FrameworkElement element = sender as FrameworkElement;
            trackingMouseMove = false;
            element.ReleaseMouseCapture();

            mousePosition.X = mousePosition.Y = 0;
            element.Cursor = null;
        }
 }
}