Asp.net上传文件后台通过二进制流发送到其他Url保存

实际情况一般有单独的站点存放静态文件，比如图片、office文档等。A站点的操作需要上传文件到B站点，

下面介绍一种方法通过System.Net.WebClient类的UploadData方法 。

uploadFile.aspx html：

<form id="form1" runat="server">
    <div>
        <asp:FileUpload runat="server" ID="fileUp" AllowMultiple="true" /> 
        <asp:Button runat="server" ID="btnLoad" Text="Upload" OnClick="btnLoad_Click" />
    </div>
    </form>

uploadFile.cs 后台代码

 protected void btnLoad_Click(object sender, EventArgs e)
        {
            if (fileUp.HasFile)
            {
                var list = fileUp.PostedFiles;
                foreach (var item in list)
                {
                    string fileDoc = System.IO.Path.GetExtension(item.FileName).ToLower(); //后缀名
                    int fileLength = (int)item.InputStream.Length;//InputStream.Length;

                    byte[] byteFile = new byte[fileLength];
                    item.InputStream.Read(byteFile, 0, fileLength);
                    item.InputStream.Seek(0, System.IO.SeekOrigin.Begin); //读取流之后设置设置当前流的位置，因为md5加密也需要用到该流

                    string md5Value =  Com.MD5.MyMD5.getMd5Hash(item.InputStream); //得到上传文件流的MD5string url = string.Format("http://localhost:4884/SaveFile.ashx?name=" + md5Value + "&ext=" + fileDoc);  //保存流的处理文件路径

                    System.Net.WebClient wc = new System.Net.WebClient();
                    byte[] bts = wc.UploadData(url, "POST", byteFile);
                    wc.Dispose();
                    string filePath = System.Text.Encoding.UTF8.GetString(bts); //获取SaveFile.ashx返回
                }
            }
        }

Com.MD5.MyMD5.getMd5Hash方法请看：我的C# MD5摘要算法、哈希算法

SaveFile.ashx 处理程序

 /// <summary>
    /// SaveFile 的摘要说明
    /// </summary>
    public class SaveFile : IHttpHandler
    {

        public void ProcessRequest(HttpContext context)
        {
            lock (context.Request.InputStream)
            {
                HttpRequest Request = context.Request;
                string path = ""; string filenName = "";
                string re = "";
                if (Request.HttpMethod.ToLower() == "post")
                {
                    try
                    {
                        using (Request.InputStream)
                        {
                            string name = Request["name"];
                            string s = Request["ext"];
                            byte[] bytes = new byte[Request.InputStream.Length];
                            Request.InputStream.Read(bytes, 0, bytes.Length); 
                            Request.InputStream.Seek(0, SeekOrigin.Begin);//设置当前流的位置
                            //Request.InputStream.Position = 0;
                            Request.InputStream.Flush();
                            Request.InputStream.Close();
                            Request.InputStream.Dispose();
                            Random rnd = new Random();
                            int n = rnd.Next(1000, 9999);
                            //filenName = "/file/" + n.ToString() + "-" + DateTime.Now.ToString("yyyyMMddHHmmssss") + s;
                            filenName = "/file/"+name + s;
                            path = context.Server.MapPath(filenName);

                            FileStream fs = new FileStream(path, FileMode.Create);
                            BinaryWriter bw = new BinaryWriter(fs);
                            bw.Write(bytes);
                            bw.Close();
                            fs.Close();
                            re = filenName;

                           //System.Threading.Thread.Sleep(500);
                        }
                    }
                    catch (Exception ex)
                    {
                        
                    }
                }

                context.Response.ContentType = "text/plain";
                context.Response.Write(re);
                context.Response.End();
            }
        }

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

HttpFileCollection：

   void save(HttpRequest Request)
        {
            var file = Request.Files[0];
            var filenName = "/file/" + file.FileName;
            var path = HttpContext.Current.Server.MapPath(filenName);
            file.SaveAs(path);
        }