title: Javascript to set hidden form value on drop down change
body: <p>New to javascript, but I'm sure this is easy.  Unfortunately, most of the google results haven't been helpful.</p>
  
  <p>Anyway, I want to set the value of a hidden form element through javascript when a drop down selection changes.</p>
  
  <p>I can use jQuery, if it makes it simpler to get or set the values.</p>