In some cases you may need to check if a domain name is IDN (Internationalized domain name) or not.
This function can do it for you (from PHP 5.3+):
//Check if a domain name is IDN or not.
//Return true of the $name is IDN or false of not.
public function is_idn($name)
{
if(idn_to_utf8($name) != $name)
return true;
return false;
}
Then you can call the function ‘is_idn’ as above:
is_idn('xn--5dbhaeldc2j.com');