title: copy label text to input
body: <p>I have tried several ways to achieve this, but somehow nothing works for this.</p>
  
  <p>How can I copy the "label text" of respective Radio Button, which is selected by user into the input field (Result Box) in real time? </p>
  
  <p>HTML - </p>
  
  <pre><code>&lt;ul class="gfield_radio" id="input_4_4"&gt;
      Radio Buttons:  
      &lt;br /&gt;
      &lt;li class="gchoice_4_0"&gt;
          &lt;input name="input_4" type="radio" value="2" id="choice_4_0" class="radio_s" tabindex="4"&gt;
          &lt;label for="choice_4_0"&gt;Hi&lt;/label&gt;
      &lt;/li&gt;
      &lt;li class="gchoice_4_1"&gt;
          &lt;input name="input_4" type="radio" value="4" id="choice_4_1" class="radio_s" tabindex="5"&gt;
          &lt;label for="choice_4_1"&gt;Hello&lt;/label&gt;
      &lt;/li&gt;
      &lt;li class="gchoice_4_2"&gt;
          &lt;input name="input_4" type="radio" value="3" id="choice_4_2" class="radio_s" tabindex="6"&gt;
          &lt;label for="choice_4_2"&gt;Aloha&lt;/label&gt;
      &lt;/li&gt;
  &lt;/ul&gt;
  &lt;br /&gt;
  &lt;div class="ginput_container"&gt;
      Result Box: 
      &lt;br /&gt;
      &lt;input name="input_3" id="input_4_3" type="text" value="" class="medium" tabindex="3"&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>My attempts:</p>
  
  <pre><code>$('input').change(function() { 
      if (this.checked) { 
          var response = $('label[for="' + this.id + '"]').html(); 
          alert(response); 
      } 
  
      // also this:
   //   if ($("input[type='radio'].radio_s").is(':checked')) { 
   //       var card_type = $("input[type='radio'].radio_s:checked").val();               
   //       alert('card_type'); 
   //   } 
  });
  </code></pre>