Silverlight中通過調用WebService來顯示資料庫中以流形式儲存的圖片

在Web開發中，常見的做法如下：

將資料庫中讀取出來的內容以位元組數組的形式儲存，字串型轉位元組數組的方法是Convert.FromBase64String,然後以二進位寫的方法將圖片資訊寫在頁面中。主要代碼如下：

SWDM dm = new SWDM();protected void Page_Load(object sender, EventArgs e){    string strSQL = "select picContent from tb_ssxq where OBJECTID=1";    DataSet ds = dm.getsql(strSQL);    byte[] byteFileStream = Convert.FromBase64String(ds.Tables[0].Rows[0]["picContent"].ToString());    Response.BinaryWrite(byteFileStream);    Response.End();}

在Silverlight中如何?呢，其實差不多，只不過在WebService中的方法的傳回值要是byte[]類型，然後在Silverlight中利用MemoryStream來接收並儲存圖片流資訊，然後將其作為BitmapImage的Source即可，最後利用Silverlight的Image控制項即可顯示出該圖片。

WebService中的代碼如下:

     /// <summary>    /// 根據險情ID擷取即時險情的圖片資訊    /// </summary>    /// <param name="paramCity"></param>    /// <returns></returns>    [WebMethod(Description = "擷取某一個即時險情的圖片資訊")]    public byte[] getSSXPictureQByID(string xqid)    {        byte[] byteFileStream = null;        string strSQL = "select picContent  from tb_ssxq where OBJECTID=" + int.Parse(xqid);        DataSet ds = dm2.getsql(strSQL);        byteFileStream = Convert.FromBase64String(ds.Tables[0].Rows[0]["picContent"].ToString());        return byteFileStream;    }

Silverlight中代碼：

<Grid x:Name="LayoutRoot" Background="White">   <Border BorderBrush="#FF5BB0FF" BorderThickness="1" Margin="0">         <Image x:Name="Image1" Margin="0" Stretch="None"/>   </Border></Grid>

private void UserControl_Loaded(object sender, RoutedEventArgs e){        //擷取險情圖片資訊        getPictureInfoSoapClient client = new getPictureInfoSoapClient();        client.getSSXPictureQByIDCompleted += new EventHandler<getSSXPictureQByIDCompletedEventArgs>(client_getSSXPictureQByIDCompleted);        client.getSSXPictureQByIDAsync(id);}//險情圖片void client_getSSXPictureQByIDCompleted(object sender, getSSXPictureQByIDCompletedEventArgs e){        MemoryStream ms = new MemoryStream(e.Result);        BitmapImage image = new BitmapImage();        image.SetSource(ms);        this.Image1.Source = image;}