php显示指定目录下子目录的方法

<?php
echo "<h2>subdirs in dir</h2><ul>";
$basedir = basename( __FILE__ );
$dirtoscan = ($basedir . '/somedir/');
$albumlisting = scandir($dirtoscan);
foreach ($albumlisting as $item) {
  $dirinfo = pathinfo($item);
  print_r($dirinfo);
  if (is_dir("$item")) {
   echo "<li><a href='index.php?subdirs=$item'>$item</a></li>";
  }
}
?>