title: jQuery Problems with removing event handler with .off()
body: <p>I have tried to remove an event handler with <code>.off()</code>, but it does not work. </p>
  
  <p>I want to remove all event handlers from one certain input:</p>
  
  <pre><code>&lt;input type="file" id="file_upload" name="file_upload" size="50" /&gt;
  </code></pre>
  
  <p>Here is what I have tried:</p>
  
  <pre><code>$('#form').on('keyup change', ':input', function() {
      registerChange();
  });
  $('#form input[name=file_upload]').off();
  $('#file_upload').off();
  </code></pre>