/**
* Extracts the BC from an IBAN
*
* @param IBAN $iban
*
* @throws \InvalidArgumentException When the supplied IBAN is not from Switzerland
*/
public static function fromIBAN(IBAN $iban)
{
if ($iban->getCountry() !== 'CH') {
throw new \InvalidArgumentException('BC can only be extracted from Swiss IBANs.');
}
return new self(substr($iban->normalize(), 4, 5));
}
