用soap调用带有验证的webservice,该怎么写？

[7年]

webservice代码：

        //定义报头
        public MySoapHeader soapheader;
        [SoapHeader("soapheader", Direction = SoapHeaderDirection.In)]
        [WebMethod]
        public string SaveUser(string userxml)
        {
            if (soapheader == null)
            {
                return "认证失败";
            }
            string msg = "";
            if (soapheader.IsValid(soapheader.UserID,soapheader.Password,out msg) == false)
            {
                return "认证失败:用户名或密码错误";
            }
            string a = "bbbb";
            return a;
        }

调用代码：

            _xmlNamespaces[URL] = XmlNs;//加入缓存，提高效率  
            HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(URL);

            if (!string.IsNullOrEmpty(userName))
            {
               // request.Method = "HEAD";
                request.PreAuthenticate = true;
                NetworkCredential cre = new NetworkCredential(userName, passWord);
                request.Credentials = cre;
            }
            else
            {
                request.Credentials = CredentialCache.DefaultCredentials;

            }

            request.Method = "POST";
            request.ContentType = "text/xml; charset=utf-8 ";
            request.Headers.Add("SOAPAction", "\"" + XmlNs + (XmlNs.EndsWith("/") ? "" : "/") + MethodName + "\"");
            //soapheader验证
            
            request.Timeout = 10000;

            // SetWebRequest(request);

            //byte[] data = EncodeParsToSoap(Pars, XmlNs, MethodName);

            Hashtable ht = new Hashtable();
            ht["UserID"] = userName;
            ht["Password"] = passWord;

            byte[] data = EncodeParsToSoap(Pars, XmlNs, MethodName, ht, XmlNs, "MySoapHeader");



            WriteRequestData(request, data);
            XmlDocument doc = new XmlDocument(), doc2 = new XmlDocument();
            doc = ReadXmlResponse(request.GetResponse());

            XmlNamespaceManager mgr = new XmlNamespaceManager(doc.NameTable);
            mgr.AddNamespace("soap", "http://schemas.xmlsoap.org/soap/envelope/");
            String RetXml = doc.SelectSingleNode("//soap:Body/*/*", mgr).InnerXml;
            doc2.LoadXml("<root>" + RetXml + "</root>");
            AddDelaration(doc2);
            return doc2;

这么写服务器断的soapheader一直是null