title: set var value from input field value
body: <p>I started short time ago with JSP, JSTL, HTML and JavaScript so here is my problem:</p>
  
  <p>I need to set the value of a var the value of an input hidden. Other option is if it possible to compare using</p>
  
  <pre><code>&lt;c:if test="...."&gt;
  </code></pre>
  
  <p>the value of a variable that I sent with the request with the value of the hidden input.</p>
  
  <p>Thanks.</p>
  
  <p><strong>Update</strong></p>
  
  <p>I've been trying but can't make it work.</p>
  
  <p>I have this field that contains the id of and object. I also have the list with the objects so what I have to do is find the object related to that ID.</p>
  
  <pre><code>&lt;input type="text" name="id1" /&gt;
  </code></pre>
  
  <p>but if I do this:</p>
  
  <pre><code>&lt;c:set var="dd" value="${param.id1}" /&gt;
  &lt;input type="text" value="${dd}" /&gt;
  </code></pre>
  
  <p>The input text is empty but the text related to id1 displays 850 (i.e. the value is dinamic)</p>
  
  <p>Any suggestion why is not working?</p>
  
  <p><strong>Update 2</strong></p>
  
  <p>I need the "multipart/form-data" because in the form I need to upload a picture. I understand how to get the parameters from Java, but since I'm not using the server but the JSP pages, there's any way to do it? Just need to read that input element and save it in a variable.</p>