public function toXMLString()
 {
     $str = '';
     $str .= '<ns:DoMobileCheckoutPaymentReq>';
     if ($this->DoMobileCheckoutPaymentRequest != NULL) {
         $str .= '<ns:DoMobileCheckoutPaymentRequest>';
         $str .= $this->DoMobileCheckoutPaymentRequest->toXMLString();
         $str .= '</ns:DoMobileCheckoutPaymentRequest>';
     }
     $str .= '</ns:DoMobileCheckoutPaymentReq>';
     return $str;
 }
 public function toXMLString()
 {
     $str = '';
     $str .= '<urn:DoMobileCheckoutPaymentReq>';
     if ($this->DoMobileCheckoutPaymentRequest != null) {
         //prop is not a collection
         //prop is complex
         //prop is not enum
         //does not contain attribute or is attribute
         $str .= '<urn:DoMobileCheckoutPaymentRequest>';
         $str .= $this->DoMobileCheckoutPaymentRequest->toXMLString();
         $str .= '</urn:DoMobileCheckoutPaymentRequest>';
     }
     $str .= '</urn:DoMobileCheckoutPaymentReq>';
     return $str;
 }