c# - dynamically call soap web service

WebRequest request = WebRequest.Create(webserviceName);
                request.Timeout = 60000;
                HttpWebResponse response = (HttpWebResponse)request.GetResponse();
                Stream dataStream = response.GetResponseStream();
                StreamReader reader = new StreamReader(dataStream);
                output = reader.ReadToEnd();
                xml.LoadXml(output);
                output = xml.GetElementsByTagName("resultTobeReturned")[0].InnerText;
                reader.Close();
                dataStream.Close();
                response.Close();