JBZoo\Utils\Email::checkDns PHP Method

    public static function checkDns($email)
    {
        if (!self::_isValid($email)) {
            return false;
        }
        $domain = self::_extractDomain($email);
        if (checkdnsrr($domain, "MX") === false) {
            return false;
        }
        return true;
    }