.net 写xml文件

      XmlDocument xmlDoc=new XmlDocument();
            xmlDoc.Load("XML/XMLDoc/ForWrite.xml");
            XmlNode root=xmlDoc.SelectSingleNode("data");//查找
            root.RemoveAll();

            string sql = " ";
            DataTable dt = SqlHelper04.ExecuteDt(sql);
            //xe1.AppendChild(xesub3);              
          
            foreach(DataRow dr in dt.Rows)
            {

                XmlElement xe1 = xmlDoc.CreateElement("rq");//创建一个节点
                xe1.SetAttribute("value", dr["rq"].ToString());//设置该节点属性

                xe1.SetAttribute("yksf", dr["pj"].ToString());//设置该节点属性
                xe1.SetAttribute("ykyt", dr["pj"].ToString());//设置该节点属性
                xe1.SetAttribute("ykpw", dr["pj"].ToString());
                xe1.SetAttribute("jkpw", dr["pj"].ToString());
                xe1.SetAttribute("wkpw", dr["pj"].ToString());

                root.AppendChild(xe1);

            }
            xmlDoc.Save("XML/XMLDoc/ForWrite.xml");