title: onblur event not working on <input> element
body: <p>I have a field on a form that is hidden but pulls data from another field to fill it in. Yet when I have tried it it does not work. I need to use <code>class</code> not <code>id</code> to fill the field.</p>
  
  <p><strong>Field with onblur Event</strong></p>
  
  <pre><code> &lt;input name="EmailAddress" type="text" class="cat_textbox" id="EmailAddress" 
         onblur="document.getElementByClass('Username2').value=this.value;" 
         maxlength="255" /&gt;
  </code></pre>
  
  <p><strong>Field That Is Being Filled</strong></p>
  
  <pre><code> &lt;input type="text" class="Username2" id="Username" name="Username" /&gt;
  </code></pre>