[WebMethod(Description = "在线更新软件")]
        public string GetUpdateData()
        {
            //取得更新的xml模板内容
            XmlDocument doc = new XmlDocument();
            doc.Load(Server.MapPath("update.xml"));
            XmlElement root = doc.DocumentElement;
            //看看有几个文件需要更新
            XmlNode updateNode = root.SelectSingleNode("filelist");
            string path = updateNode.Attributes["sourcepath"].Value;
            int count = int.Parse(updateNode.Attributes["count"].Value);
            //将xml中的value用实际内容替换
            for (int i = 0; i < count; i++)
            {
                XmlNode itemNode = updateNode.ChildNodes[i];
                string fileName = path + itemNode.Attributes["name"].Value;
                FileStream fs = File.OpenRead(Server.MapPath(fileName));
                itemNode.Attributes["size"].Value = fs.Length.ToString();
                BinaryReader br = new BinaryReader(fs);
                //这里是文件的实际内容，使用了Base64String编码
                itemNode.SelectSingleNode("value").InnerText = Convert.ToBase64String(br.ReadBytes((int)fs.Length), 0, (int)fs.Length);
                br.Close();
                fs.Close();
            }
            return doc.InnerXml;
        }



      public void update()
        {
            WebSvs.Service1 webs = new WebSvs.Service1();
 [color=#FF0000]           System.Xml.XmlDocument doc = new XmlDocument();[color]
 string xml= webs.GetUpdateData();[/color]

doc.LoadXml(xml);
          
            doc.Save(Application.StartupPath + @"\update.xml");
            System.Diagnostics.Process.Start(Application.StartupPath + @"\update.exe");
            Close();
            Application.Exit();
        }