How to get response in mvc3 when html5 based file upload success

See more:

C#

HTML5

MVC3

I want display response value when file is uploaded succesfuly...
my code is ...

  <form class="form1" enctype="multipart/form-data" method="post" action="@Url.Action("Upload")" >
                	<input id="fileToUpload1" name="fileToUpload1" type="file"/>
                    <div style="width:500px;">
                    <div id="Mydiv"></div>
                    <progress id="progressBar" value="0" max="100">  </progress>  
                    
                    </div>
               
				
                 </form>

<script type="text/javascript">
  // File load event
				            xhr.upload.addEventListener("load", loadSuccess, false);

				            function loadSuccess(evt) {
                              //here i want to display response result
				             //  alert("Response");
                                }

controller is...

[HttpPost]
      public ActionResult Upload(object fileToUpload1)
      {

              int sucessid= 101;
              return Json(sucessid, JsonRequestBehavior.AllowGet);
       }

and that succes id i want to display on upload success event of view...Controller return that value but not display in alert of load event handler method...