public function toPKIRequestString()
{
return RequestStringBuilder::create()->append("cardAlias", $this->getCardAlias())->append("cardNumber", $this->getCardNumber())->append("expireYear", $this->getExpireYear())->append("expireMonth", $this->getExpireMonth())->append("cardHolderName", $this->getCardHolderName())->getRequestString();
}