PHP遍历某个目录下的所有文件和子文件夹

<?phpfunction read_all_dir ( $dir )    {        $result = array();        $handle = opendir($dir);        if ( $handle )        {            while ( ( $file = readdir ( $handle ) ) !== false )            {                if ( $file != '.' && $file != '..')                {                    $cur_path = $dir . DIRECTORY_SEPARATOR . $file;                    if ( is_dir ( $cur_path ) )                    {                        $result['dir'][$cur_path] = read_all_dir ( $cur_path );                    }                    else                    {                        $result['file'][] = $cur_path;                    }                }            }            closedir($handle);        }        return $result;    }?>