title: Populate hidden form element value with the value of a text field on form submit (jQuery)
body: <p>I want to automatically populate a hidden form element with the value of what is entered in a single line text field in a form when submitted. How would this be done with jQuery? Thanks for any suggestions.</p>
  
  <pre><code>&lt;form&gt;
  &lt;input type="hidden" id="username" name="username" value="" /&gt;
  &lt;input type="text" id="email" name="email" value="some.email@typed.here.on.webpage.com" /&gt;
  &lt;input type="submit" value="Submit" class="submit" /&gt;
  &lt;/form&gt;
  </code></pre>