sql数据转为XML

        Database db = DataClass.getDataBase();
        DataTable dt = DataClass.LoadDataTable(" select [Y_Site_id], [Y_Site_name], [Y_Site_marker], [Y_Site_address],[Y_Site_X], [Y_Site_Y],[Y_Site_rain],[Y_Site_waterposition] from Y_Site", "tablesite", db);

        XmlDocument xd = new XmlDocument();
        XmlDeclaration xde;
        xde = xd.CreateXmlDeclaration("1.0", "UTF-8", null);
        xd.AppendChild(xde);

        XmlElement map1 = xd.CreateElement("map");
        xd.AppendChild(map1);

        XmlElement nc1 = xd.CreateElement("nc");
        map1.AppendChild(nc1);

        XmlNode nc = xd.SelectSingleNode("nc");

        if (dt.Rows.Count > 0)
        {
            for (int i = 0; i < dt.Rows.Count; i++)
            {
                XmlElement xe1 = xd.CreateElement("p" + i.ToString());
                xe1.SetAttribute("Y_Site_id", dt.Rows[i]["Y_Site_id"].ToString());
                xe1.SetAttribute("Y_Site_name", dt.Rows[i]["Y_Site_name"].ToString());
                xe1.SetAttribute("Y_Site_marker", dt.Rows[i]["Y_Site_marker"].ToString());
                xe1.SetAttribute("x1", dt.Rows[i]["Y_Site_X"].ToString());
                xe1.SetAttribute("y1", dt.Rows[i]["Y_Site_Y"].ToString());
                nc1.AppendChild(xe1);
            }
        }
        xd.Save(Server.MapPath("xmlData/getdata.xml"));