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