php 正则html网址代码

$pattern = "/[w-] .(com|net|org|gov|cc|biz|info|cn)(.(cn|hk))*/";
    preg_match($pattern, $url, $matches);
    if(count($matches) > 0) {
        返回$matches[0];
    }其他{
        $rs = parse_url($url);
        $main_url = $rs["主机"];
        if(!strcmp(long2ip(sprintf("%u",ip2long($main_url))),$main_url)) {
            返回 $main_url;
        }其他{
            $arr = Explode(".",$main_url);
            $count=count($arr);
            $endArr = array("com","net","org","3322");//com.cn  net.cn 等情况
            if (in_array($arr[$count-2],$endArr)){
                $domain = $arr[$count-3].".".$arr[$count-2].".".$arr[$count-1];
            }其他{
                $domain = $arr[$count-2].".".$arr[$count-1];
            }
            返回 $domain;
        }// 结束 if(!strcmp...)
    }// 结束 if(count...)