Silverlight中大图片的加载进度

使用System.Windows.Media.Imaging.BitmapImage类的DownloadProgress事件，再配合ProgressBar等控件即可做出进度条效果，下面代码中就只简单的使用TextBlock显示进度

1、MainPage.xaml代码

<Grid x:Name="LayoutRoot" Background="White">
    <Image  x:Name="img"/>
    <TextBlock  Text="正在加载 0%" x:Name="TxtLoading" HorizontalAlignment="Center" Foreground="Black" VerticalAlignment="Center" />
</Grid>

2、MainPage.xaml.cs代码

public partial class MainPage : UserControl
{
    BitmapImage bitmapImage;

    public MainPage()
    {
        InitializeComponent();
        this.Loaded += new RoutedEventHandler(MainPage_Loaded);
    }

    private void MainPage_Loaded(object sender, RoutedEventArgs e)
    {
        bitmapImage = new BitmapImage();
        img.Source = bitmapImage;
        bitmapImage.UriSource = new Uri("http://192.168.178.222/test.jpg");
        img.Stretch = Stretch.Fill;
        bitmapImage.DownloadProgress += new EventHandler<DownloadProgressEventArgs>(bitmapImage_DownloadProgress);
    }

    private void bitmapImage_DownloadProgress(object sender, DownloadProgressEventArgs e)
    {
        TxtLoading.Text = string.Format("正在加载 {0}%", e.Progress);
    }
}