prototype javascript library Form extend example

<form action="form_submit" id="f1" method="post" accept-charset="utf-8">
 <p><input type="text" name="test1" value="test1" id="test1"></p>
 <p><input type="text" name="test2" value="test2" id="test2"></p>
 <p>
  <select id="s1" name="s1">
   <option>1</option>
   <option>2</option>
   <option>3</option>
   <option>4</option>
  </select>
 </p>
 <p><input type="submit" value="submit"></p>
</form>
<script type="text/javascript" charset="utf-8">
function doc(argument) {
 document.write("<p>\n");
 document.write(argument);
 document.write("</p>\n");
}

//Form.disable('f1');
Form.focusFirstElement('f1');
doc($('s1').type);// select-one
</script>