title: How to get radio button value after onclick event in prototype
body: <p>I am using the following piece of code in the prototype js-</p>
  
  <pre><code> $('co-payment-form').on('change', 'input:radio', function() {
      alert(this.value);
   });
  </code></pre>
  
  <p>I want to get the radio button value after clicking the radio button. I tried this.value but value is coming undefined. Please help me how to get the value. Thanks</p>