Wordpress: DIV short code with classes and IDs

div-shortcode.php

function div_shortcode($atts, $content = null ) {
  extract(shortcode_atts(array('class' => '', 'id' => '' ), $atts));
  $return = '<div';
  if (!empty($class)) $return .= ' class="'.$class.'"';
  if (!empty($id)) $return .= ' id="'.$id.'"';
  $return .= '>'. do_shortcode($content) . '</div>';
  return $return;
}
add_shortcode('div', 'div_shortcode');