xml创建

  string sql = "select rentid from lesseeRent ";
           DataTable dt= MDGL.DBUtility.SQLServerHelper.GetDataTable(CommandType.Text,sql);
           //创建一个xml文档
           XmlDocument xmlDoc = new XmlDocument();
            //声明，一个节点
           XmlNode xmlNode = xmlDoc.CreateNode(XmlNodeType.XmlDeclaration,"","");
           xmlDoc.AppendChild(xmlNode);
            //注释
           XmlComment xmlComment = xmlDoc.CreateComment("rentID列表");
           xmlDoc.AppendChild(xmlComment);
            //创建根元素
           XmlElement xmlEle = xmlDoc.CreateElement("rentIDList");
           xmlDoc.AppendChild(xmlEle);

          //创建子元素
           XmlElement xmlEle2;
            foreach(DataRow dr in dt.Rows)
            {
                xmlEle2 = xmlDoc.CreateElement("rentID");
                XmlText xmlText = xmlDoc.CreateTextNode(dr["rentID"].ToString());
                xmlEle2.AppendChild(xmlText);//子元素添加文本内容
                xmlEle.AppendChild(xmlEle2);//父元素添加子元素
            }
            xmlDoc.Save("D:\\b.xml");//xml文档存储

 //写xml
            string sql = "select rentid from lesseeRent ";
           DataTable dt= MDGL.DBUtility.SQLServerHelper.GetDataTable(CommandType.Text,sql);
           //创建一个xml文档
           XmlDocument xmlDoc = new XmlDocument();
           StringBuilder str = new StringBuilder();
        
           str.Append("<?xml version=\"1.0\" ?>");
           str.Append("<rentList>");
           foreach (DataRow dr in dt.Rows)
           {
               str.Append("<rentID>");
               str.Append(dr["rentID"].ToString());
               str.Append("</rentID>");
           }
           str.Append("</rentList>");
           xmlDoc.LoadXml(str.ToString());
           xmlDoc.Save("D:\\a.xml");