This is PHP Class to check if given name valid domain name or not.
###history
In the pass when Domain TLDs only .com .net .org .biz .info .us to extract domain name you can use Regular expression
[-a-z0-9]{1,63}\.[a-z]{2,4}
now when more then 500 Domain TLDs registered that regex is not reliable even with if you modified like this one
[-a-z0-9]{1,63}\.([a-z]{2,4}\.)?[a-z]{2,4}
or
[a-z0-9]+([\-\.]{1}[a-z0-9]+)*\.[a-z]{2,6}
for example with regex above name cintai.anu.mu will detected as valid domain not subdomain but its wrong valid domain tlds are .mu, ac.mu, .co.mu, .com.mu, .org.mu, .net.mu
require_once("is_domain.php");
### Return True if domain valid domain, otherwise false
checkName::is_domain("example.com"); // will return "true"
### Get or Parse domain from URL
checkName::cleanURL("https://github.com/ewwink/php-domain-name-validation"); // will return "github.com"
### Get or Parse domain from URL and validate Domain name
checkName::is_domain("https://github.com/ewwink/php-domain-name-validation", true); // will return "true"
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