匹配 $gdinfo 中的数字

<?php
/*
//下载
$filename = ‘av.zip‘;

// 设置类型：可以省略
// header("content-type:image/jpeg");

//设置文件为附件
header("content-disposition:attachment;filename=".$filename);

//文件大小
header("content-length:".readfile($filename));

//输出下载
readfile($filename);
*/
//
$gd = gd_info();
$gdinfo = $gd["GD Version"];
echo $gdinfo;

$pattern = ‘/\(((.*?)\w[a-zA-Z]{1,})\)/‘;
preg_match($pattern,$gdinfo,$arr);
echo $arr[2];
//$copy = $arr[1];
//echo $copy;