Iyzipay\Request\CreateThreedsPaymentRequest::toPKIRequestString PHP Method

    public function toPKIRequestString()
    {
        return RequestStringBuilder::create()->appendSuper(parent::toPKIRequestString())->append("paymentId", $this->getPaymentId())->append("conversationData", $this->getConversationData())->getRequestString();
    }