[PHP] img태그를 li에 넣기 - preg_match_all

<ul id="ctt_ul">
<?php 
$matches = array();
preg_match_all("/<img[^>]*src=[\"']?([^>\"']+)[\"']?[^>]*>/i", $str, $matches);
for($i = 0; $i<count($matches[0]); $i++){
    echo '<li>'.$matches[0][$i].'</li>';
}; ?>
</ul>