src/lib/IBAN.php
private function isChecksumValid()
    {
        $countryCode = $this->getCountryCode();
        $checksum = $this->getChecksum();
        $accountIdentification = $this->getAccountIdentification();
        $numericCountryCode = $this->getNumericCountryCode($countryCode);
        $numericAccountIdentification = $this->getNumericAccountIdentification($accountIdentification);
        $invertedIban = $numericAccountIdentification . $numericCountryCode . $checksum;

        return $this->bcmod($invertedIban, 97) === '1';
    }
private function isChecksumValid()
    {
        $countryCode = $this->getCountryCode();
        $checksum = $this->getChecksum();
        $accountIdentification = $this->getAccountIdentification();
        $numericCountryCode = $this->getNumericCountryCode($countryCode);
        $numericAccountIdentification = $this->getNumericAccountIdentification($accountIdentification);
        $invertedIban = $numericAccountIdentification . $numericCountryCode . $checksum;

        return $this->bcmod($invertedIban, 97) === '1';
    }
private function isChecksumValid ( ) { $ countryCode = $ this -> getCountryCode ( ) ; $ checksum = $ this -> getChecksum ( ) ; $ accountIdentification = $ this -> getAccountIdentification ( ) ; $ numericCountryCode = $ this -> getNumericCountryCode ( $ countryCode ) ; $ numericAccountIdentification = $ this -> getNumericAccountIdentification ( $ accountIdentification ) ; $ invertedIban = $ numericAccountIdentification . $ numericCountryCode . $ checksum ; return $ this -> bcmod ( $ invertedIban , 97 ) === '1' ; }
Validates if the checksum number is valid according to the IBAN

@return bool
Validates if the checksum number is valid according to the IBAN