php算法-遍历文件夹

function findDir($dir){
		$handel = openDir($dir);
		$files = [];
		while(false !== ($file = readdir($handel))){
			if($file == '.' || $file == '..'){
				continue;
			}
			
			$subDir = realpath($dir.'/'.$file);
			if(is_dir($subDir)){
				$files[$subDir] = findDir($subDir);
			}else{
				$files[] = $file;
			}
			
		}
		closedir($handel);
		return $files;
	}