public function hasMx($email)
    {
        if (! $this->isEmail($email)) {
            return null;
        }

        $hostname = $this->hostnameFromEmail($email);

        if ($hostname) {
            return checkdnsrr($hostname, 'MX');
        }

        return null;
    }
public function hasMx($email)
    {
        if (! $this->isEmail($email)) {
            return null;
        }

        $hostname = $this->hostnameFromEmail($email);

        if ($hostname) {
            return checkdnsrr($hostname, 'MX');
        }

        return null;
    }
public function hasMx ( $ email ) { if ( ! $ this -> isEmail ( $ email ) ) { return null ; } $ hostname = $ this -> hostnameFromEmail ( $ email ) ; if ( $ hostname ) { return checkdnsrr ( $ hostname , 'MX' ) ; } return null ; }
Test email address for MX records

@param string $email Address
@return boolean|null
Test email address for MX records