title: Mootools - how to get value of selected radio input type, from its name
body: <p>Question 1: Given </p>
  
  <pre><code>&lt;input type="radio" name="foo" value="1" /&gt;
  &lt;input type="radio" name="foo" value="2" /&gt;
  &lt;input type="radio" name="foo" value="3" /&gt;
  </code></pre>
  
  <p>In Mootools, how do I return "2" given an input of "foo", assuming that the second radio button was clicked.</p>
  
  <hr>
  
  <p>Question 2: (it's related)- Given similar <strong>checkbox</strong> inputs, how do I return either an array or comma separated list of the checked values?</p>
  
  <p>I'm wanting to submit the values of these inputs via Request.JSON, passing it as a GET parameter.</p>