c＃如何使用HTTP POST multipart/form-data將文件上傳到ashx

Question

我試圖將大文件上傳到通用處理程序FileUpload.ashx。

我用正確的方式檢查了Fiddler數據到服務器。但我無法在服務器方面取得成功。

我嘗試了很多方法，但我無法獲取存儲在HttpContext中的數據。

我試過老

context.Request.Files[0]; 
context.Request.Params["file"] 
context.Request["file"]; 

和其他一些東西，現在即時通訊很困惑。在簡單的HTML中只設置類型文件並用上面的第一個方法進行輸入，這裏是否複雜？我是否必須爲內容編寫我自己的解析器？沒有更簡單的方法嗎？

public void ProcessRequest(HttpContext context) 
{ 
    // what to do here 
} 

誰能爲客戶端和服務器端提供樣品

順便說一句我的客戶端的WinRT和服務器端是.NET 4.5

Answer 1

您可能要檢查他們是如何做到這一點在這項目：

https://github.com/maxpavlov/jQuery-File-Upload.MVC3

這裏是處理上傳文件的接收主代碼：

using System.Collections.Generic; 
using System.IO; 
using System.Linq; 
using System.Web; 
using System.Web.Script.Serialization; 

namespace jQuery_File_Upload.MVC3.Upload 
{ 
    /// <summary> 
    /// Summary description for UploadHandler 
    /// </summary> 
    public class UploadHandler : IHttpHandler 
    { 
     private readonly JavaScriptSerializer js; 

     private string StorageRoot 
     { 
      get { return Path.Combine(System.Web.HttpContext.Current.Server.MapPath("~/Files/")); } //Path should! always end with '/' 
     } 

     public UploadHandler() 
     { 
      js = new JavaScriptSerializer(); 
      js.MaxJsonLength = 41943040; 
     } 

     public bool IsReusable { get { return false; } } 

     public void ProcessRequest(HttpContext context) 
     { 
      context.Response.AddHeader("Pragma", "no-cache"); 
      context.Response.AddHeader("Cache-Control", "private, no-cache"); 

      HandleMethod(context); 
     } 

     // Handle request based on method 
     private void HandleMethod(HttpContext context) 
     { 
      switch (context.Request.HttpMethod) 
      { 
       case "HEAD": 
       case "GET": 
        if (GivenFilename(context)) DeliverFile(context); 
        else ListCurrentFiles(context); 
        break; 

       case "POST": 
       case "PUT": 
        UploadFile(context); 
        break; 

       case "DELETE": 
        DeleteFile(context); 
        break; 

       case "OPTIONS": 
        ReturnOptions(context); 
        break; 

       default: 
        context.Response.ClearHeaders(); 
        context.Response.StatusCode = 405; 
        break; 
      } 
     } 

     private static void ReturnOptions(HttpContext context) 
     { 
      context.Response.AddHeader("Allow", "DELETE,GET,HEAD,POST,PUT,OPTIONS"); 
      context.Response.StatusCode = 200; 
     } 

     // Delete file from the server 
     private void DeleteFile(HttpContext context) 
     { 
      var filePath = StorageRoot + context.Request["f"]; 
      if (File.Exists(filePath)) 
      { 
       File.Delete(filePath); 
      } 
     } 

     // Upload file to the server 
     private void UploadFile(HttpContext context) 
     { 
      var statuses = new List<FilesStatus>(); 
      var headers = context.Request.Headers; 

      if (string.IsNullOrEmpty(headers["X-File-Name"])) 
      { 
       UploadWholeFile(context, statuses); 
      } 
      else 
      { 
       UploadPartialFile(headers["X-File-Name"], context, statuses); 
      } 

      WriteJsonIframeSafe(context, statuses); 
     } 

     // Upload partial file 
     private void UploadPartialFile(string fileName, HttpContext context, List<FilesStatus> statuses) 
     { 
      if (context.Request.Files.Count != 1) throw new HttpRequestValidationException("Attempt to upload chunked file containing more than one fragment per request"); 
      var inputStream = context.Request.Files[0].InputStream; 
      var fullName = StorageRoot + Path.GetFileName(fileName); 

      using (var fs = new FileStream(fullName, FileMode.Append, FileAccess.Write)) 
      { 
       var buffer = new byte[1024]; 

       var l = inputStream.Read(buffer, 0, 1024); 
       while (l > 0) 
       { 
        fs.Write(buffer, 0, l); 
        l = inputStream.Read(buffer, 0, 1024); 
       } 
       fs.Flush(); 
       fs.Close(); 
      } 
      statuses.Add(new FilesStatus(new FileInfo(fullName))); 
     } 

     // Upload entire file 
     private void UploadWholeFile(HttpContext context, List<FilesStatus> statuses) 
     { 
      for (int i = 0; i < context.Request.Files.Count; i++) 
      { 
       var file = context.Request.Files[i]; 

       var fullPath = StorageRoot + Path.GetFileName(file.FileName); 

       file.SaveAs(fullPath); 

       string fullName = Path.GetFileName(file.FileName); 
       statuses.Add(new FilesStatus(fullName, file.ContentLength, fullPath)); 
      } 
     } 

     private void WriteJsonIframeSafe(HttpContext context, List<FilesStatus> statuses) 
     { 
      context.Response.AddHeader("Vary", "Accept"); 
      try 
      { 
       if (context.Request["HTTP_ACCEPT"].Contains("application/json")) 
        context.Response.ContentType = "application/json"; 
       else 
        context.Response.ContentType = "text/plain"; 
      } 
      catch 
      { 
       context.Response.ContentType = "text/plain"; 
      } 

      var jsonObj = js.Serialize(statuses.ToArray()); 
      context.Response.Write(jsonObj); 
     } 

     private static bool GivenFilename(HttpContext context) 
     { 
      return !string.IsNullOrEmpty(context.Request["f"]); 
     } 

     private void DeliverFile(HttpContext context) 
     { 
      var filename = context.Request["f"]; 
      var filePath = StorageRoot + filename; 

      if (File.Exists(filePath)) 
      { 
       context.Response.AddHeader("Content-Disposition", "attachment; filename=\"" + filename + "\""); 
       context.Response.ContentType = "application/octet-stream"; 
       context.Response.ClearContent(); 
       context.Response.WriteFile(filePath); 
      } 
      else 
       context.Response.StatusCode = 404; 
     } 

     private void ListCurrentFiles(HttpContext context) 
     { 
      var files = 
       new DirectoryInfo(StorageRoot) 
        .GetFiles("*", SearchOption.TopDirectoryOnly) 
        .Where(f => !f.Attributes.HasFlag(FileAttributes.Hidden)) 
        .Select(f => new FilesStatus(f)) 
        .ToArray(); 

      string jsonObj = js.Serialize(files); 
      context.Response.AddHeader("Content-Disposition", "inline; filename=\"files.json\""); 
      context.Response.Write(jsonObj); 
      context.Response.ContentType = "application/json"; 
     } 

    } 
}