public XmlDataDocument GetSiteAData(string AssignName)  {    XmlDataDocument xd = new XmlDataDocument();    DataSet ds = BusinessWork.BusinessWorkDataSet("TreeView1");      xd = new XmlDataDocument(ds);      XmlNode root1 = xd.DocumentElement;      XmlNodeList roots = root1.SelectNodes("url");      foreach (XmlNode roota in roots) //為所有元素加上站點名稱標記      {        XmlElement Link = xd.CreateElement("SiteName");        Link.InnerText = ConfigurationSettings.AppSettings["SiteName"].ToString();        roota.AppendChild(Link);      }    return xd;  }

  IAsyncResult ar1;    IAsyncResult ar2;    localhost.WebService serviceA = new localhost.WebService();    XmlNode xmlNode1;    XmlNode xmlNode2;    ////直接調用    //xmlNode1 = serviceA.GetSiteAData("2");    //異步調用    ar1 = serviceA.BeginGetSiteAData("3", null, null);    ar2 = serviceA.BeginGetSiteAData("2", null, null);    xmlNode1 = serviceA.EndGetSiteAData(ar1);    xmlNode2 = serviceA.EndGetSiteAData(ar2);    StringBuilder xmlString1;    xmlString1 = new StringBuilder(xmlNode1.OuterXml);    XmlDataDocument xd = new XmlDataDocument();    xd.LoadXml(xmlString1.ToString());    DataSet ds = new DataSet();    ds.ReadXml(new XmlNodeReader(xd));    GridView1.DataSource = ds.Tables[0];    GridView1.DataBind();