title: Does form with enctype="multipart/form-data" cause problems accessing a hidden field
body: <p>I have created a hidden form element</p>
  
  <pre><code>&lt;form name="UploadImage" enctype="multipart/form-data" method="post" action="UploadImage"&gt;
      &lt;label&gt;
          &lt;/label&gt;
      &lt;input name="imgUploadObjId" id="imgUploadObjId" value="52" type="hidden"&gt;
  
      //rest of the form here
  
  &lt;/form&gt;
  </code></pre>
  
  <p>And I am trying to get the value with this line in a servlet (as I have done before):</p>
  
  <pre><code>int objId = Integer.parseInt(request.getParameter("imgUploadObjId"));
  </code></pre>
  
  <p>But I get this (line 33 is the line above):</p>
  
  <blockquote>
    <p>java.lang.NumberFormatException: null<br>
                java.lang.Integer.parseInt(Unknown Source)
        java.lang.Integer.parseInt(Unknown Source)
        web.objects.UploadImage.doPost(UploadImage.java:33)
        javax.servlet.http.HttpServlet.service(HttpServlet.java:637)
        javax.servlet.http.HttpServlet.service(HttpServlet.java:717)</p>
  </blockquote>
  
  <p>Is there something different about a form with enctype="multipart/form-data"? Or can you see some other error.</p>