title: How to submit additional data along the file upload in dropzone.js?
body: <p>I have this form in my html code:</p>
  
  <pre><code>&lt;form action="upload" id="upload-dropzone" class="dropzone"&gt;
      &lt;input type="hidden" name="browser-path" id="browser-path" value="/"&gt;
  
      &lt;div class="browser-buttons rrtl"&gt;
          &lt;a id="browser-btn-upload"&gt;Upload&lt;/a&gt;
      &lt;/div&gt;
  
      &lt;div class="lltr" id="browser-path-view"&gt;&lt;/div&gt;
  &lt;/form&gt;
  
  &lt;script type="application/javascript"&gt;
      Dropzone.options.uploadDropzone = {
          clickable: "#browser-btn-upload",
      };
      loadBrowserContent();
  &lt;/script&gt;
  </code></pre>
  
  <p>As <a href="https://github.com/enyo/dropzone/wiki/FAQ#how-to-submit-additional-data-along-the-file-upload" rel="nofollow">this document</a> said, the hidden input field <code>browser-path</code> will automatically be submitted as POST data to server.</p>
  
  <p>I have this code in my server side:</p>
  
  <pre><code>System.out.println(request.getParameter("browser-path"));
  </code></pre>
  
  <p>But this code always prints <code>null</code> to output!</p>
  
  <p>How can I submit this hidden field to my server and how can I read it?</p>
  
  <p><strong>Edit:</strong></p>
  
  <p>Thanks to steeno, the form <code>enctype</code> is <code>multipart/form-data</code> so I have to read the fields from another way.</p>