UPNP.UPnP.GetServiceAndEventURL C# (CSharp) Method

        private bool GetServiceAndEventURL(string descriptionURL)
        {

            XmlDocument description = new XmlDocument();
            WebRequest webRequest = WebRequest.Create(descriptionURL);

            try
            {
                // rufe Device Description ab
                description.Load(webRequest.GetResponse().GetResponseStream());

                XmlNamespaceManager xmlNSManager = new XmlNamespaceManager(description.NameTable);
                xmlNSManager.AddNamespace("ns", "urn:schemas-upnp-org:device-1-0");

                // Internet Gateway Device?
                XmlNode deviceTypeNode = description.SelectSingleNode("//ns:device/ns:deviceType/text()", xmlNSManager);
                if (!deviceTypeNode.Value.Contains("InternetGatewayDevice"))
                    return false;

                // suche Service URL
                XmlNode serviceURLNode = description.SelectSingleNode("//ns:service[ns:serviceType=\"urn:schemas-upnp-org:service:WANIPConnection:1\"]/ns:controlURL/text()", xmlNSManager);
                if (serviceURLNode == null)
                    return false;
                else
                    m_ServiceURL = BuildURL(descriptionURL, serviceURLNode.Value);

                // suche Event URL
                XmlNode eventURLNode = description.SelectSingleNode("//ns:service[ns:serviceType=\"urn:schemas-upnp-org:service:WANIPConnection:1\"]/ns:eventSubURL/text()", xmlNSManager);
                if (eventURLNode == null)
                    return false;
                else
                    m_EventURL = BuildURL(descriptionURL, eventURLNode.Value);

                return true;
            }
            catch (Exception e)
            {
                throw e;
            }

        }