public function toXMLString() { $str = ''; $str .= '<ns:SetCustomerBillingAgreementReq>'; if ($this->SetCustomerBillingAgreementRequest != null) { $str .= '<ns:SetCustomerBillingAgreementRequest>'; $str .= $this->SetCustomerBillingAgreementRequest->toXMLString(); $str .= '</ns:SetCustomerBillingAgreementRequest>'; } $str .= '</ns:SetCustomerBillingAgreementReq>'; return $str; }