title: dropzone.js and ASP.NET MVC file posted is null?
body: <p>I am trying to use dropzone.js to upload images in my ASP.NET MVC app. I am able to set-up the dropzone programatically, click on it, select the image and when I click "Open" in the file dialog, the correct Action is hit in the controller. However, the HttpPostedFileBase always comes back as null so I can't do anything with the image. ON the client-side, however, it shows the image thumbnail correctly, eventhough I can't get it on the server side.</p>
  
  <p>This is the HTML:</p>
  
  <pre><code>&lt;div style="float:left;margin-right:2px;" id="mainImage"&gt;
      &lt;img src="/images/AddImage_button.png" class="dz-message" /&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>This is the js code I call after the doc is ready:</p>
  
  <pre><code>var myDropzone = new Dropzone("div#mainImage", { url: "/Market/UploadImage" });
  </code></pre>
  
  <p>And this is the action call inside of the controller:</p>
  
  <pre><code>public ContentResult UploadImage(HttpPostedFileBase imageFile)
  {
  
      if (imageFile == null || imageFile.ContentLength == 0)
      {
      //.....
      }
  }
  </code></pre>
  
  <p>The action is hit but imageFile is null. Does anyone has any ideas? By the way, the "dz-message" class was added in the image placeholder inside the dropzone because before that it was not clickable. I read it somewhere that was a fix for that issue and it worked.</p>
  
  <p>Any ideas why I am getting null for imageFile?</p>