title: Get value of checked radio button
body: <pre><code>&lt;input type="radio" id="radio1" name="radiobuttons" value="100"&gt;
  &lt;input type="radio" id="radio2" name="radiobuttons" value="200"&gt;
  &lt;input type="radio" id="radio3" name="radiobuttons" value="300"&gt;
  
  
  &lt;div id="selectedvalue"&gt;&lt;/div&gt;
  </code></pre>
  
  <p>How do I get value of the checked radio button and output it as text inside "selectedvalue" ? The function should take the value of the checked radio on pageload and on input change.</p>