不通过“添加引用服务”调用WebService接口

      有时候，在调用外网的服务时，例如Webservice服务，直接添加引用服务，有时候还要手动更新服务，比较不够智能，如果能只通过传入服务地址和参数就能获取数据，那就最好不过。

     以下就是一个例子：

        public static XElement WebCallRequestFunc(string paramXML)
        {
            try
            {
                System.Net.ServicePointManager.DefaultConnectionLimit = 200;
                System.Net.HttpWebRequest req = System.Net.HttpWebRequest.Create("*.asmx") as System.Net.HttpWebRequest;//回呼服务地址 
                System.Text.Encoding encoding = System.Text.Encoding.UTF8;//默认编码
                string paras = string.Format("<s:Envelope xmlns:s=\"http://schemas.xmlsoap.org/soap/envelope/\"><s:Header><h:SoapHeaderExt xmlns:h=\"http://tempuri.org/\" xmlns=\"http://tempuri.org/\" xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xmlns:xsd=\"http://www.w3.org/2001/XMLSchema\"><UserToken>{0}</UserToken></h:SoapHeaderExt></s:Header><s:Body xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xmlns:xsd=\"http://www.w3.org/2001/XMLSchema\"><ArticleGeneration xmlns=\"http://tempuri.org/\"><xml>{1}</xml></ArticleGeneration></s:Body></s:Envelope>","",paramXML);//xml格式参数
                byte[] bs = System.Text.Encoding.UTF8.GetBytes(paras);
                req.Host = "";
                req.Method = "POST";
                req.UserAgent = "Mozilla-Firefox-Spider(Wenanry)";
                req.Timeout = 30000;
                req.Headers.Add("SOAPAction","http://tempuri.org/ArticleGeneration");
                req.Headers.Add("VsDebuggerCausalityData",""); 
                //req.Headers.Add("Expect","100-continue"); 
                //req.CookieContainer = new System.Net.CookieContainer();
                //System.Net.CookieContainer cookie = new System.Net.CookieContainer();//如果用不到Cookie，删去即可  
                req.KeepAlive = true;
                //上面的http头看情况而定，但是下面俩必须加  
                req.ContentType = "text/xml;charset=utf-8";
                req.ContentLength = bs.Length;
                using (System.IO.Stream reqStream = req.GetRequestStream())
                {
                    reqStream.Write(bs,bs.Length);
                    reqStream.Close();
                }
                string responseData = string.Empty;//返回数据
                using (System.Net.HttpWebResponse response = (req.GetResponse() as System.Net.HttpWebResponse))
                { //如果http头中接受gzip的话，这里就要判断是否为有压缩，有的话，直接解压缩即可  
                    #region 读取内容
                    //req.CookieContainer.Add(response.Cookies);
                    System.IO.Stream responseStream = response.GetResponseStream();
                    using (System.IO.StreamReader reader = new System.IO.StreamReader(responseStream,encoding))
                    {
                        responseData = reader.ReadToEnd();
                    }
                    if (!string.IsNullOrEmpty(responseData))
                    {
                        //string decsponseData = Server.HtmlDecode(responseData);
                        Regex reg = new Regex("<ArticleGenerationResult>.*</ArticleGenerationResult>",RegexOptions.IgnoreCase);//返回
                        MatchCollection matches = reg.Matches(responseData);
                        XElement xmlDoc = null;
                        if (matches.Count > 0)
                        {
                            xmlDoc = XElement.Parse(matches[0].Value); //如果是xml字符串，则用以下形式
                        }
                        return xmlDoc;
                    }
                    else
                    {
                        return null;
                    }
                    #endregion
                }//using
            }
            catch (Exception ex)
            {
                return null;
            }
        }