Silverlight结合Web Service进行文件上传

search了非常多的文章，总算勉强实现了。有许多不完善的地方。

在HCLoad.Web项目下新建目录Pics复制一张图片到根目录下。

图片名：Bubble.jpg 右击->属性->生成操作：Resource

UC_UpDown.xaml

<UserControl x:Class="HCLoad.UC_UpDown"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
    Width="500" Height="500">
    <StackPanel Background="White" Height="450">
        <Button Content="down" Click="Button_Click"></Button>
        <HyperlinkButton Content="下载保存" NavigateUri="http://localhost:4528/download.ashx?fileName=aa.txt" TargetName="_self" x:Name="lBtnDown" />
        <TextBlock x:Name="tbMsgString" Text="下载进度" TextAlignment="Center" Foreground="Green"></TextBlock>
        <Button x:Name="btnDownload" Content="DownLoad Pictures" Width="150" Height="35" Margin="15" Click="btnDownload_Click"/>
        <Border Background="Wheat" BorderThickness="5" Width="400" Height="280">
            <Image x:Name="imgDownLoad" Width="400" Height="300" Margin="15" Stretch="Fill"/>
        </Border>
        <Button x:Name="btnUpLoad" Content="UpLoad Pictures" Width="150" Height="35" Margin="15" Click="btnUpLoad_Click"/>
    </StackPanel>
</UserControl>

UC_UpDown.xaml.cs

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.Windows.Media.Imaging; //因为要使用BitmapImage
using System.IO;  //因为要使用Stream

namespace HCLoad
{
    public partial class UC_UpDown : UserControl
    {
        //1、WebClient 对象一次只能启动一个请求。如果在一个请求完成（包括出错和取消）前，即IsBusy为true时，进行第二个请求，则第二个请求将会抛出 NotSupportedException 类型的异常
        //2、如果 WebClient 对象的 BaseAddress 属性不为空，则 BaseAddress 与 URI（相对地址） 组合在一起构成绝对 URI
        //3、WebClient 类的 AllowReadStreamBuffering 属性：是否对从 Internet 资源接收的数据做缓冲处理。默认值为true，将数据缓存在客户端内存中，以便随时被应用程序读取



        //获取选定图片信息
        System.IO.FileInfo fileinfo;
        public UC_UpDown()
        {
            InitializeComponent();
        }
        #region  下载图片
        private void btnDownload_Click(object sender, RoutedEventArgs e)
        {
            //向指定的Url发送下载流数据请求 
            String imgUrl = "http://localhost:4528/Bubble.jpg";
            Uri endpoint = new Uri(imgUrl);

            WebClient client = new WebClient();
            client.OpenReadCompleted += new OpenReadCompletedEventHandler(OnOpenReadCompleted);
            client.DownloadProgressChanged += new DownloadProgressChangedEventHandler(clientDownloadStream_DownloadProgressChanged);
            client.OpenReadAsync(endpoint);
        }
        void OnOpenReadCompleted(object sender, OpenReadCompletedEventArgs e)
        {

            //OpenReadCompletedEventArgs.Error - 该异步操作期间是否发生了错误
            //OpenReadCompletedEventArgs.Cancelled - 该异步操作是否已被取消
            //OpenReadCompletedEventArgs.Result - 下载后的 Stream 类型的数据
            //OpenReadCompletedEventArgs.UserState - 用户标识

            if (e.Error != null)
            {
                MessageBox.Show(e.Error.ToString());
                return;
            }
            if (e.Cancelled != true)
            {
                //获取下载的流数据(在此处是图片数据)并显示在图片控件中
                //Stream stream = e.Result;
                //BitmapImage bitmap = new BitmapImage();
                //bitmap.SetSource(stream);
                //imgDownLoad.Source = bitmap;
                Stream clientStream = e.UserState as Stream;
                Stream serverStream = (Stream)e.Result;
                byte[] buffer = new byte[serverStream.Length];
                serverStream.Read(buffer, 0, buffer.Length);
                clientStream.Write(buffer, 0, buffer.Length);
                clientStream.Close();
                serverStream.Close();

            }



        }

        void clientDownloadStream_DownloadProgressChanged(object sender, DownloadProgressChangedEventArgs e)
        {
            //DownloadProgressChangedEventArgs.ProgressPercentage - 下载完成的百分比
            //DownloadProgressChangedEventArgs.BytesReceived - 当前收到的字节数
            //DownloadProgressChangedEventArgs.TotalBytesToReceive - 总共需要下载的字节数
            //DownloadProgressChangedEventArgs.UserState - 用户标识

            this.tbMsgString.Text = string.Format("完成百分比：{0} 当前收到的字节数：{1} 资料大小：{2} ",
              e.ProgressPercentage.ToString() + "%",
              e.BytesReceived.ToString(),
              e.TotalBytesToReceive.ToString());

        }

        #endregion

        #region  上传图片
        private void btnUpLoad_Click(object sender, RoutedEventArgs e)
        {
            /**/
            /*
         *　　 OpenWriteCompleted - 在打开用于上传的流完成时（包括取消操作及有错误发生时）所触发的事件
         *　　 WriteStreamClosed - 在写入数据流的异步操作完成时（包括取消操作及有错误发生时）所触发的事件
         *　　 UploadProgressChanged - 上传数据过程中所触发的事件。如果调用 OpenWriteAsync() 则不会触发此事件
         *　　 Headers - 与请求相关的的标头的 key/value 对**
         *　　 OpenWriteAsync(Uri address, string method, Object userToken) - 打开流以使用指定的方法向指定的 URI 写入数据
         *　　　　 Uri address - 接收上传数据的 URI
         *　　　　 string method - 所使用的 HTTP 方法（POST 或 GET）
         *　　　　 Object userToken - 需要上传的数据流
         */


            OpenFileDialog openFileDialog = new OpenFileDialog()
            {  //弹出打开文件对话框要求用户自己选择在本地端打开的图片文件
                Filter = "Jpeg Files (*.jpg)|*.jpg|All Files(*.*)|*.*",
                Multiselect = false  //不允许多选 
            };

            if (openFileDialog.ShowDialog() == true)//.DialogResult.OK)
            {
                //fileinfo = openFileDialog.Files; //取得所选择的文件，其中Name为文件名字段，作为绑定字段显示在前端
                fileinfo = openFileDialog.File;

                if (fileinfo != null)
                {
                    WebClient webclient = new WebClient();

                    string uploadFileName = fileinfo.Name.ToString(); //获取所选文件的名字

                    #region 把图片上传到服务器上

                    Uri upTargetUri = new Uri(String.Format("http://localhost:4528/WebClientUpLoadStreamHandler.ashx?fileName={0}", uploadFileName), UriKind.Absolute); //指定上传地址

                    webclient.OpenWriteCompleted += new OpenWriteCompletedEventHandler(webclient_OpenWriteCompleted);
                    webclient.Headers["Content-Type"] = "multipart/form-data";

                    webclient.OpenWriteAsync(upTargetUri, "POST", fileinfo.OpenRead());
                    webclient.WriteStreamClosed += new WriteStreamClosedEventHandler(webclient_WriteStreamClosed);

                    #endregion

                }
                else
                {
                    MessageBox.Show("请选取想要上载的图片!!!");
                }
            }

        }



        void webclient_OpenWriteCompleted(object sender, OpenWriteCompletedEventArgs e)
        {

            //将图片数据流发送到服务器上

            // e.UserState - 需要上传的流（客户端流）
            Stream clientStream = e.UserState as Stream;
            // e.Result - 目标地址的流（服务端流）
            Stream serverStream = e.Result;
            byte[] buffer = new byte[4096];
            int readcount = 0;
            // clientStream.Read - 将需要上传的流读取到指定的字节数组中
            while ((readcount = clientStream.Read(buffer, 0, buffer.Length)) > 0)
            {
                // serverStream.Write - 将指定的字节数组写入到目标地址的流
                serverStream.Write(buffer, 0, readcount);
            }
            serverStream.Close();
            clientStream.Close();


        }

        void webclient_WriteStreamClosed(object sender, WriteStreamClosedEventArgs e)
        {
            //判断写入是否有异常
            if (e.Error != null)
            {
                System.Windows.Browser.HtmlPage.Window.Alert(e.Error.Message.ToString());
            }
            else
            {
                System.Windows.Browser.HtmlPage.Window.Alert("图片上传成功!!!");
            }
        }
        #endregion

        private void Button_Click(object sender, RoutedEventArgs e)
        {
            //这种方法搞不定，好像提示跨域操作。
            //提示：错误：Unhandled Error in Silverlight Application 跨线程访问无效。
            //Uri upTargetUri = new Uri(String.Format("http://localhost:4528/download.ashx?filename={0}", "123.jpg"), UriKind.Absolute); //指定上传地址
            //WebRequest request = WebRequest.Create(upTargetUri);
            //request.Method = "GET";
            //request.ContentType = "application/octet-stream";
            //request.BeginGetResponse(new AsyncCallback(RequestReady), request);

            //通过调用js代码下载，比较简单。
            System.Windows.Browser.HtmlPage.Window.Eval("window.location.href='http://localhost:4528/download.ashx?filename=123.jpg';");
        }
        void RequestReady(IAsyncResult asyncResult)
        {
            MessageBox.Show("RequestComplete");
        }

    }
}

在HCLoad.Web项目下新建WebClientUpLoadStreamHandler.ashx

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

using System.IO;  //因为要用到Stream

namespace HCLoad.Web
{
    public class WebClientUpLoadStreamHandler : IHttpHandler
    {

        public void ProcessRequest(HttpContext context)
        {
            //获取上传的数据流
            string fileNameStr = context.Request.QueryString["fileName"];
            Stream sr = context.Request.InputStream;
            try
            {
                string filename = "";

                filename = fileNameStr;

                byte[] buffer = new byte[4096];
                int bytesRead = 0;
                //将当前数据流写入服务器端文件夹ClientBin下
                string targetPath = context.Server.MapPath("Pics/" + filename + ".jpg");
                using (FileStream fs = File.Create(targetPath, 4096))
                {
                    while ((bytesRead = sr.Read(buffer, 0, buffer.Length)) > 0)
                    {
                        //向文件中写信息
                        fs.Write(buffer, 0, bytesRead);
                    }
                }

                context.Response.ContentType = "text/plain";
                context.Response.Write("上传成功");
            }
            catch (Exception e)
            {
                context.Response.ContentType = "text/plain";
                context.Response.Write("上传失败, 错误信息:" + e.Message);
            }
            finally
            { sr.Dispose(); }

        }

        public bool IsReusable
        {
            get
            {
                return false;
            }
        }
    }

}

新建download.ashx

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Services;
using System.Net;

namespace HCLoad.Web
{
    /// <summary>
    /// $codebehindclassname$ 的摘要说明
    /// </summary>
    public class download : IHttpHandler
    {
        private long ChunkSize = 102400;//100K 每次读取文件，只读取100Ｋ，这样可以缓解服务器的压力

        public void ProcessRequest(HttpContext context)
        {
            //string fileName = "123.jpg";//客户端保存的文件名
            String fileName = context.Request.QueryString["filename"]; 
            string filePath = context.Server.MapPath("Bubble.jpg");
            System.IO.FileInfo fileInfo = new System.IO.FileInfo(filePath);
            if (fileInfo.Exists == true)
            {
                byte[] buffer = new byte[ChunkSize];
                context.Response.Clear();
                System.IO.FileStream iStream = System.IO.File.OpenRead(filePath);
                long dataLengthToRead = iStream.Length;//获得下载文件的总大小
                context.Response.ContentType = "application/octet-stream";
                //通知浏览器下载文件而不是打开
                context.Response.AddHeader("Content-Disposition", "attachment;  filename=" + HttpUtility.UrlEncode(fileName, System.Text.Encoding.UTF8));
                while (dataLengthToRead > 0 && context.Response.IsClientConnected)
                {
                    int lengthRead = iStream.Read(buffer, 0, Convert.ToInt32(ChunkSize));//读取的大小
                    context.Response.OutputStream.Write(buffer, 0, lengthRead);
                    context.Response.Flush();
                    dataLengthToRead = dataLengthToRead - lengthRead;
                }
                context.Response.Close();
                context.Response.End();
            }
            //context.Response.ContentType = "text/plain";
            //context.Response.Write("Hello World");
        }

        public bool IsReusable
        {
            get
            {
                return false;
            }
        }
    }
}

参考：
http://www.cnblogs.com/wsdj-ittech/archive/2009/08/26/1554056.html
http://www.cnblogs.com/wsdj-ittech/archive/2009/08/25/1553534.html
http://www.cnblogs.com/wmt1708/archive/2009/03/07/1405009.html
http://topic.csdn.net/u/20090918/10/5e41ab52-f514-46b5-ae6a-d69ddb197213.html
http://www.cnblogs.com/wsdj-ittech/archive/2009/08/25/1553534.html
http://www.cnblogs.com/gwazy/archive/2009/04/02/1427781.html
http://www.cnblogs.com/ewyb/archive/2009/12/10/1621020.html
http://blog.csdn.net/emily1900/archive/2010/06/08/5655726.aspx

凡事以大气象去面对，优秀是一种习惯。

 

分类: SilverLight

标签: Silverlight