php如何获取文件夹里所有avi文件?

<?php
$path = ".";
$ext = ".css";

function get_filetree($path, $ext)
{
$tree = array();
$temp = glob($path . "/*" . $ext);
if($temp) $tree = array_merge($tree, $temp);
foreach (glob($path . "/*", GLOB_ONLYDIR) as $dir) {
$temp = get_filetree($dir, $ext);
if($temp) $tree = array_merge($tree, $temp);
}

return $tree;
}

//print_r(get_filetree($path, $ext));
$list = get_filetree($path, $ext);
foreach($list as $item) {
echo "".$file = basename($item)."
";
}