在Silverlight中读取指定URL图片包数据

<Grid x:Name="LayoutRoot" Background="White">
    <Grid.RowDefinitions>
        <RowDefinition Height="250" />
        <RowDefinition Height="100" />
        <RowDefinition Height="50" />
    </Grid.RowDefinitions>
    <StackPanel Grid.Row="1">
        <ListBox x:Name="ImageList"/>
        <Button x:Name="Download" Click="StartDownLoad" Content="下载该图片"/>
    </StackPanel>
    <StackPanel Grid.Row="0">            
        <ScrollViewer HorizontalScrollBarVisibility="Auto" >
            <Image x:Name="ImgToFill" >           
            </Image>
        </ScrollViewer>
    </StackPanel>
    <StackPanel Grid.Row="2">
        <Canvas Canvas.Top="70" >
            <Rectangle  Name="progressRectangle" Height="10" Width="0" Fill="AliceBlue" />
            <Rectangle Height="12"  Width="202" StrokeThickness="1" Stroke="Black" />
            <TextBlock x:Name="progressText" Canvas.Left="210" Text="0%" FontSize="12" />
        </Canvas>
    </StackPanel>
</Grid>

　　接下来是page.xaml.cs(相关内容见注释):

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;

using System.IO;
using System.Windows.Resources;
using System.Windows.Media.Imaging;

namespace DownLoadImg
{
    public partial class Page : UserControl
    {
        WebClient wc = new WebClient();

        public Page()
        {
            InitializeComponent();
            this.Loaded += new RoutedEventHandler(Page_Loaded);
        }

        //加载图片列表数据
        void Page_Loaded(object sender, RoutedEventArgs e)
        {
            ImageList.Items.Add("1.jpg");
            ImageList.Items.Add("2.png");
        }
        //实例化下载设置
        void StartDownLoad(object o, EventArgs e)
        {
            //初始化相应控件信息
            ImgToFill.Visibility = Visibility.Collapsed;
            progressRectangle.Width = 0;
            progressText.Text = "0%";
            //绑定下载过程中处理的事件
            wc.OpenReadCompleted += new OpenReadCompletedEventHandler(wc_OpenReadCompleted);
            wc.DownloadProgressChanged += new DownloadProgressChangedEventHandler(wc_DownloadProgressChanged);
            //开始异步读取压缩包中的文件信息
            wc.OpenReadAsync(new Uri("img.zip", UriKind.Relative), ImageList.SelectedItem);
        }
        
        void wc_OpenReadCompleted(object sender, OpenReadCompletedEventArgs e)
        {
           //实例化流资源信息，准备获取其中的图片数据
            StreamResourceInfo sri = new StreamResourceInfo(e.Result as Stream, null);
            //要读取的图片路径信息
            String sURI = e.UserState as String;
            //从流资源中获取指定的URL图片流信息
            StreamResourceInfo imageStream = Application.GetResourceStream(sri, new Uri(sURI, UriKind.Relative));
            BitmapImage imgsrc = new BitmapImage();
            //绑定该URL图片信息并进行显示
            imgsrc.SetSource(imageStream.Stream);
            ImgToFill.Source = imgsrc;
            ImgToFill.Visibility = Visibility.Visible;
            ImgToFill.Stretch = Stretch.Fill;
        }

        void wc_DownloadProgressChanged(object sender, DownloadProgressChangedEventArgs e)
        {
            //下载过程中的进度显示
            progressText.Text = e.ProgressPercentage.ToString() + "%";
            progressRectangle.Width = (double)e.ProgressPercentage * 2;
        }

    }
}