• Silverlight 实现文件上传

    通过web进行文件上传，一般要使用form表单，在silverlight里面没有内置form表单功能，参考牛人文章，实现Silverlight文件上传。只要Web.config文件中httpRuntime节点的maxRequestLength属性足够大，上传就不受限制。

    项目结构图：


    MainPage类源码:

    View Code 
      1 namespace SilverlightDownAndUploadFile
  2 {
  3     public partial class MainPage : UserControl
  4     {
  5         private OpenFileDialog ofd;
  6         private AutoResetEvent autoEvent = new AutoResetEvent(false);
  7 
  8         public MainPage()
  9         {
 10             InitializeComponent();
 11         }
 12 
 13         private static HttpWebRequest CreateWebRequest(string requestUriString, string httpMethod)
 14         {
 15             try
 16             {
 17                 string ticks = Guid.NewGuid().ToString();
 18                 requestUriString = requestUriString + "/" + ticks;
 19                 HttpWebRequest request = (HttpWebRequest)WebRequestCreator.ClientHttp.Create(new Uri(requestUriString));
 20                 request.Method = httpMethod;
 21 
 22                 return request;
 23             }
 24             catch (Exception ex)
 25             {
 26                 return null;
 27             }
 28         }
 29         #region 上传
 30 
 31         private void ReadFileToRequestStream(BinaryReader fileStream, HttpWebRequest request)
 32         {
 33             try
 34             {
 35                 request.BeginGetRequestStream((requestAsyncResult) =>
 36                 {
 37                     Stream requestStream = null;
 38                     try
 39                     {
 40                         requestStream = request.EndGetRequestStream(requestAsyncResult);
 41                         if (null != requestStream)
 42                         {
 43                             SilverlightMultipartFormData form = new SilverlightMultipartFormData();
 44                             //form.AddFormField("devilField", "中国人");
 45                             int maxBufferLen = 25 * 1024;
 46                             byte[] buffer = new byte[maxBufferLen];
 47                             int bytesRead = fileStream.Read(buffer, 0, maxBufferLen);
 48                             int i = 0;
 49                             while (bytesRead != 0)
 50                             {
 51                                 i++;
 52                                 byte[] newBuffer = GetNewBuffer(buffer, bytesRead);
 53                                 form.AddStreamFile("package" + i, "package" + i, newBuffer);
 54                                 buffer = new byte[maxBufferLen];
 55                                 bytesRead = fileStream.Read(buffer, 0, maxBufferLen);
 56                             }
 57 
 58                             form.PrepareFormData();//结束
 59                             fileStream.Close();
 60                             request.ContentType = "multipart/form-data; boundary=" + form.Boundary;
 61                             foreach (byte byt in form.GetFormData())
 62                             {
 63                                 requestStream.WriteByte(byt);
 64                             }
 65                             requestStream.Close();
 66                             autoEvent.Set();//开始上传
 67                         }
 68                     }
 69                     catch (Exception ex)
 70                     { }
 71                     finally
 72                     {
 73                         if (null != requestStream)
 74                             requestStream.Close();
 75                         if (null != fileStream)
 76                             fileStream.Close();
 77                     }
 78                 }, null);
 79             }
 80             catch (Exception ex)
 81             {
 82 
 83             }
 84         }
 85 
 86         private void RequestAndUploadFile(BinaryReader br)
 87         {
 88             try
 89             {
 90                 if (null == br) return;
 91                 HttpWebRequest request = CreateWebRequest("http://localhost:13953/Upload.ashx", "POST");
 92                 ReadFileToRequestStream(br, request);
 93                 autoEvent.WaitOne();//等待流写入完毕
 94 
 95                 //上传
 96                 request.BeginGetResponse(
 97                             (asyncResult) =>
 98                             {
 99                                 if (request.HaveResponse)
100                                 {
101                                     try
102                                     {
103                                         WebResponse response = request.EndGetResponse(asyncResult);
104 
105                                         Stream responseStream = response.GetResponseStream();
106                                         int bufferLen = 1024;
107                                         byte[] buffer = new byte[bufferLen];
108                                         int bytesRead = responseStream.Read(buffer, 0, bufferLen);
109                                         responseStream.Close();
110 
111                                         string responseText = System.Text.Encoding.UTF8.GetString(buffer, 0, bytesRead);
112 
113                                         ShowUploadResult(true);
114                                     }
115                                     catch (Exception ex)
116                                     {
117                                         ShowUploadResult(false);
118                                     }
119                                 }
120                             }, null);
121             }
122             catch (Exception ex)
123             {
124                 ShowUploadResult(false);
125             }
126         }
127 
128         private void btnUpload_Click(object sender, RoutedEventArgs e)
129         {
130             ofd = new OpenFileDialog();
131             ofd.Filter = "(*.rar)|*.rar";
132             ofd.Multiselect = false;
133 
134             if (ofd.ShowDialog() == true)
135             {
136                 uploadProgress.Visibility = Visibility.Visible;
137                 BinaryReader br = new BinaryReader(ofd.File.OpenRead());
138                 RequestAndUploadFile(br);
139             }
140         }
141 
142         private void ShowUploadResult(bool isSucess)
143         {
144             this.Dispatcher.BeginInvoke(
145                 () =>
146                 {
147                     uploadProgress.Visibility = Visibility.Collapsed;
148                     if (isSucess)
149                         MessageBox.Show("上传成功");
150                     else
151                         MessageBox.Show("上传失败.");
152                 });
153         }
154         #endregion
155 
156         /// <summary>
157         /// 获了实际接读取到的字节数组
158         /// </summary>
159         /// <param name="buffer"></param>
160         /// <param name="bytesRead"></param>
161         /// <returns></returns>
162         private byte[] GetNewBuffer(byte[] buffer, int bytesRead)
163         {
164             byte[] newBuffer = new byte[bytesRead];
165             for (int i = 0; i < bytesRead; i++)
166             {
167                 newBuffer[i] = buffer[i];
168             }
169             return newBuffer;
170         }
171     }
172 }

    Upload.ashx文件源码:

    View Code 
      1 namespace SilverlightDownAndUploadFile.Web
  2 {
  3     /// <summary>
  4     /// Upload 的摘要说明
  5     /// </summary>
  6     public class Upload : IHttpHandler
  7     {
  8 
  9         public void ProcessRequest(HttpContext context)
 10         {
 11             //context.Response.ContentType = "text/plain";
 12             //context.Response.Write("Hello World");
 13             Stream stream = null;
 14             try
 15             {
 16                 string path = context.Server.MapPath("~/Files/upload.rar");
 17                 int i = 0;
 18                 while (true)
 19                 {
 20                     i++;
 21                     string packageName = "package" + i;
 22                     HttpPostedFile uploadFile = context.Request.Files[packageName];
 23                     if (null != uploadFile)
 24                     {
 25                         stream = context.Request.Files[packageName].InputStream;
 26                         FileStream fs = null;
 27                         if (i == 1 && File.Exists(path))
 28                         {
 29                             fs = new FileStream(path, FileMode.Create, FileAccess.Write);
 30                         }
 31                         else
 32                         {
 33                             fs = new FileStream(path, FileMode.Append, FileAccess.Write);
 34                         }
 35 
 36                         using (BinaryWriter bw = new BinaryWriter(fs))
 37                         {
 38                             int maxBufferLen = 20 * 1024;//20K
 39                             byte[] buffer = new byte[maxBufferLen];
 40                             int bytesRead = stream.Read(buffer, 0, maxBufferLen);
 41                             while (bytesRead != 0)
 42                             {
 43                                 byte[] newBuff = GetNewBuffer(buffer, bytesRead);
 44                                 bw.Write(newBuff, 0, newBuff.Length);
 45 
 46                                 buffer = new byte[maxBufferLen];
 47                                 bytesRead = stream.Read(buffer, 0, maxBufferLen);
 48                             }
 49 
 50                             //返回本次上传字节数
 51                             context.Response.Write(stream.Length);
 52                             context.Response.Flush();
 53                         }
 54 
 55                         stream.Close();
 56                         fs.Close();
 57                     }
 58                     else
 59                     {
 60                         if (i != 1)
 61                             break;
 62                         else
 63                             i = 0;
 64                     }
 65                 }
 66 
 67                 context.Response.Write("Upload Success!");
 68                 context.Response.Flush();
 69                 context.Response.End();
 70             }
 71             catch (Exception ex)
 72             {
 73             }
 74             finally
 75             {
 76                 if (null != stream)
 77                     stream.Close();
 78             }
 79         }
 80 
 81         /// <summary>
 82         /// 获取实际读取到的字节数组
 83         /// </summary>
 84         /// <param name="buffer"></param>
 85         /// <param name="bytesRead"></param>
 86         /// <returns></returns>
 87         private byte[] GetNewBuffer(byte[] buffer, int bytesRead)
 88         {
 89             byte[] newBuffer = new byte[bytesRead];
 90             for (int i = 0; i < bytesRead; i++)
 91             {
 92                 newBuffer[i] = buffer[i];
 93             }
 94             return newBuffer;
 95         }
 96 
 97         public bool IsReusable
 98         {
 99             get
100             {
101                 return false;
102             }
103         }
104     }
105 }

    完整源码可从http://download.csdn.net/detail/lianchangshuai/4998494下载。
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  • 原文地址：https://www.cnblogs.com/liancs/p/2863020.html
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