I'm trying to upload a file using Ajax.BeginForm(), but it's not working out.

My view contains:

@using (Ajax.BeginForm(UploadFile, null, new AjaxOptions { HttpMethod=POST,     UpdateTargetId = result }, new { enctype = multipart/form-data }))

{

   <label id=lblUploadNewFile for=fileUploadControl>Upload New File&lt;/label>

   <input type=file name=fileToUpload id=fileUploadControl/>

   <input id=btnFileUpload type=submit value=Upload />

   <span id=result />

}

and the corresponding Controller is:

[HttpPost]

public string UploadFile(FormCollection formData)

{

   HttpPostedFileBase file=null;



   try

   {

      file = Request.Files[0];

   }

   catch { }



   if ( file!=null && file.ContentLength > 0)

   {

      file.SaveAs(string.Concat(

            AppDomain.CurrentDomain.BaseDirectory,

            Path.GetFileName(file.FileName)));



      return "Successfully Uploaded";

   }

   else

   {

      return "Upload Failed, please try again.";

   }

}

The problem is that it's uploading the file, but no longer doing any asynchronous posts when I remove jquery.unobtrusive-ajax.js. Instead, it does a full post-back.

When I add jquery.unobtrusive-ajax.js in my view, it's doing it asynchronously, but it is not sending an upload file in the form data. No file is being sent to the server in Request.Files[].