sliverlight实现文件的上传与下载

（1）实现上传附件

silverlight端代码：

 private void button1_Click(object sender, RoutedEventArgs e)
        {
            OpenFileDialog dialog = new OpenFileDialog();
            if (dialog.ShowDialog().Value)
            {
                // 选择上传的文件
                FileInfo file = dialog.File;
                Stream stream = file.OpenRead();
                stream.Position = 0;
                byte[] buffer = new byte[stream.Length + 1];
                //将文件读入字节数组
                stream.Read(buffer, 0, buffer.Length);
                String fileExtention = file.Extension;
                //调用服务上传
                ServiceReference1.UploadFileSoapClient upfile = new UploadFileSoapClient();
                upfile.UploadfileAsync(buffer, fileExtention);
                upfile.UploadfileCompleted += new EventHandler<UploadfileCompletedEventArgs>(upfile_UploadfileCompleted);
              
            }
            else
            {
                MessageBox.Show("请选择文件！");
            }           
        } 
           void upfile_UploadfileCompleted(object sender, UploadfileCompletedEventArgs e)
            {              
                 MessageBox.Show("上传成功！");
            }

 

　　webservice代码：

[WebMethod]
        public int Uploadfile(byte[] FileByte, string FileExtention)
        {
            //文件存放路径
            string filepath = string.Format(@"D:\example{0}", FileExtention);
            //如果文件已经存在则删除
            if (File.Exists(filepath))
                File.Delete(filepath);
            //创建文件流实例，用于写入文件
            FileStream stream = new FileStream(filepath, FileMode.CreateNew);
            //写入文件
            stream.Write(FileByte, 0, FileByte.Length);
            stream.Close();
            return FileByte.Length;
        }

（2）

    public void UploadFile(EBillType eBillType,int nBillID, byte[] arrFileByte, string sFileName, string sFileType, string sRemarks)
        {
            FileStream objFileStream = null;
            try
            {

                // 以时间命名文件夹
                sFileName = sFileName.Substring(0, sFileName.LastIndexOf(".") - 1) + (DateTime.Now.ToString("yyyyMMddhhssmm"));
                //文件存放路径
                string sFilePath = string.Format(@"D:\MyWork\MRP系统\MRP\MRPService\MRPService\Files\{0}{1}", sFileName, sFileType);     

                //String fileExtention = file.Extension;
                //sFileType = sFileType.Substring(sFileType.LastIndexOf(".") + 1).ToLower();
                //调用服务上传支持的文件格式
                if (sFileType != ".xls" && sFileType != ".doc" && sFileType !=".pdf")
                {
                    throw new Exception("上传文件格式不支持！");
                }
                //如果文件已经存在则删除
                if (File.Exists(sFilePath))
                    File.Delete(sFilePath);
                //创建文件流实例，用于写入文件
                //string sWebConfig = System.Configuration.ConfigurationSettings.AppSettings["AttachDbFilename"];
                //string sWebConfig = "D:\MyWork\MRP系统\MRP\MRPService\MRPService";

                objFileStream = new FileStream( sFilePath, FileMode.CreateNew);
                //写入文件
                objFileStream.Write(arrFileByte, 0, arrFileByte.Length);
                objFileStream.Close();

                //保存到数据库
                CUploadFile objUploadFile = new CUploadFile(eBillType, nBillID, base.LogUserID, base.LogUserName, base.LogUserCode, base.LogDeptID, base.LogDeptName);
                objUploadFile.FileName = sFileName;
                objUploadFile.FilePath = sFilePath;
                objUploadFile.FileSize = arrFileByte.Length;
                objUploadFile.FileType = sFileType;

                UploadFileDAL.Save(objUploadFile);

            }
            catch (Exception ex)
            {
                throw ex;
            }
            finally
            {
                objFileStream = null;
            }
        }

下载文件：

public void ProcessRequest(HttpContext context)
        {
            String fileName = context.Request.QueryString["fileName"]; //客户端保存的文件名
            fileName=HttpUtility.UrlDecode(fileName);
            String filePath = context.Server.MapPath("data/" + fileName); //路径
            FileInfo fileInfo = new FileInfo(filePath);
            if (fileInfo.Exists)
            {
                byte[] buffer = new byte[102400];
                context.Response.Clear();

                FileStream iStream = File.OpenRead(filePath);
                long dataLengthToRead = iStream.Length; //获取下载的文件总大小

                context.Response.ContentType = "application/octet-stream";
                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(102400));//'读取的大小

                    context.Response.OutputStream.Write(buffer, 0, lengthRead);
                    context.Response.Flush();
                    dataLengthToRead = dataLengthToRead - lengthRead;
                }
                context.Response.Close();
                context.Response.End();

            }

        }

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

 

当我们新建玩这个类的时候，就可以在你点击下载的按钮那里写事件来调用这个类进行下载文件！但是条件是你的文件是存在固定的一个文件夹中的.只有找到路径才可以下载的。

               private void HyperlinkButton_Click(object sender, RoutedEventArgs e)
        {
                       string fileaddressofneeded = “1.txt”;//需要下载的文件名字

            HyperlinkButton hlbutton = sender as HyperlinkButton;
            var client = new WebClient();           
            var u= new Uri(String.Format("{0}/http://www.cnblogs.com/Handler/DownLoadFileHandler.ashx?FileName={1}" ,client.BaseAddress, fileaddressofneeded),UriKind.RelativeOrAbsolute);
            hlbutton.NavigateUri = u;
        }