PHP正则表达式从url中取得域名

function get_domain($url){ $pattern = "/[/w-]+/.(com|net|org|gov|cc|biz|info|cn)(/.(cn|hk))*/"; preg_match($pattern, $url, $matches); if(count($matches) > 0) { return $matches[0]; }else{ $rs = parse_url($url); $main_url = $rs["host"]; if(!strcmp(long2ip(sprintf("%u",ip2long($main_url))),$main_url)) { return $main_url; }else{ $arr = explode(".",$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]; }else{ $domain = $arr[$count-2].".".$arr[$count-1]; } return $domain; }// end if(!strcmp...) }// end if(count...) }// end function