刪除多餘文件

<?php
function my_dir($dir) {
        $files = [];
        if(@$handle = opendir($dir)) {
                while(($file = readdir($handle)) !== false) {
                        if($file != ".." && $file != ".") {
                                if(is_dir($dir . "/" . $file)) { //如果是子文件夾，進行遞歸
                                        $files[$file] = my_dir($dir . "/" . $file);
                                } else {
                                        $files[] = $file;
                                }
                        }
                }
        closedir($handle);
    }
        return $files;
}
$files = my_dir("./photo");
$conn = new mysqli('localhost', 'name', 'password', 'dbname');
$arr = array();
foreach($files as $k=>$v){
        foreach($v as $ks=>$vs){
                if(is_array($vs)){
                        foreach($vs as $kss=>$vss){
                                $str = strtolower(substr($vss, strrpos($vss, '.')+