获取没有TLD的域名

I have this code right here:

    // get host name from URL
    preg_match('@^(?:http://)?([^/]+)@i',
    "http://www.joomla.subdomain.php.net/index.html", $matches);
    $host = $matches[1];

    // get last two segments of host name
    preg_match('/[^.]+\.[^.]+$/', $host, $matches);
    echo "domain name is: {$matches[0]}
";

The output will be php.net

I need just php without .net

Group the first part of your 2nd regex into /([^.]+)\.[^.]+$/ and $matches[1] will be php

Although regexes are fine here, I'd recommend parse_url

$host = parse_url('http://www.joomla.subdomain.php.net/index.html', PHP_URL_HOST);
$domains = explode('.', $host);
echo $domains[count($domains)-2];

This will work for TLD's like .com, .org, .net, etc. but not for .co.uk or .com.mx. You'd need some more logic (most likely an array of tld's) to parse those out.

It's really easy:

function get_tld($domain) {
    $domain=str_replace("http://","",$domain); //remove http://
    $domain=str_replace("www","",$domain); //remowe www
    $nd=explode(".",$domain);
    $domain_name=$nd[0];
    $tld=str_replace($domain_name.".","",$domain);
    return $tld;
}

To get the domain name, simply return $domain_name, it works only with top level domain. In the case of subdomains you will get the subdomain name.