#region 全局变量
        /// <summary>
        /// XML path
        /// </summary>
        public String x_Path = String.Empty;


        /// <summary>
        /// 查询关键字 x_Name
        /// </summary>
        public String key = String.Empty;


        /// <summary>
        /// DataSet ds
        /// </summary>
        public DataSet ds = new DataSet();


        /// <summary>
        /// x_Id
        /// </summary>
        public static String x_Id = String.Empty;
        #endregion

       #region 读取数据
        /// <summary>
        /// 加载数据 one
        /// </summary>
        public void LoadXML_One()
        {
            /*
             * 此种方式绑定到 GridView 不能支持 GridView自带的分页功能，
             * 并且还不稳定，容易出错(不推荐)
             */

            //加载 XML
            XElement elements = XElement.Load(x_Path);

            try
            {
                var query = from xm in elements.Elements("ChildNodes")
                            orderby xm.Element("x_Age").Value descending
                            select new   //注意前面绑定什么字段(DataField),这里就查询什么字段
                            {
                                x_Id = xm.Attribute("x_Id").Value.Trim(),//x_Id 是属性 使用 Attribute获取
                                x_Name = xm.Element("x_Name").Value.Trim(),x_Gender = xm.Element("x_Gender").Value.Trim(),x_Age = xm.Element("x_Age").Value.Trim(),x_Address = xm.Element("x_Address").Value.Trim(),x_Tel = xm.Element("x_Tel").Value.Trim(),x_Remark = xm.Element("x_Remark").Value.Trim()
                            };

                this.gvXML.DataSource = query;
                this.gvXML.DataBind();
            }
            catch (Exception ex)
            {
                ClientScript.RegisterStartupScript(GetType(),"","alert('系统异常！具体如下：" + ex.Message.ToString() + "');",true);
            }
        }




        /// <summary>
        /// 加载数据 Two
        /// </summary>
        public void LoadXML_Two()
        {
            /*
             * 方法二比较方法一更稳定，不过有些复杂，
             * 主要是借助 Linq To DataSet的一些技术(这节知识在后面介绍),* 别且此种方法可以支持 GridView自带分页功能(推荐)
             */
            try
            {
                //加载XML文件到 ds中
                ds.ReadXml(x_Path);

                if (ds != null && ds.Tables.Count > 0)
                {
                    IEnumerable<DataRow> query = from xm in ds.Tables[0].AsEnumerable()
                                                 orderby xm.Field<String>("x_Age") descending
                                                 select xm;

                    this.gvXML.DataSource = query.CopyToDataTable();
                    this.gvXML.DataBind();
                }
            }
            catch (Exception ex)
            {
                ClientScript.RegisterStartupScript(GetType(),true);
            }
        }
        #endregion

        /// <summary>
        /// 查询方式一
        /// </summary>
        public void SearchXML_One()
        {
            XElement elements = XElement.Load(x_Path);

            var query = from xm in elements.Elements("ChildNodes")
                        where xm.Element("x_Name").Value.Contains(key)
                        orderby xm.Element("x_Age") descending
                        select new
                        {
                            x_Id = xm.Attribute("x_Id").Value.Trim(),//x_Id 是属性 使用 Attribute获取
                            x_Name = xm.Element("x_Name").Value.Trim(),x_Remark = xm.Element("x_Remark").Value.Trim()
                        };

            if (query != null)
            {
                this.gvXML.DataSource = query;
                this.gvXML.DataBind();
            }
        }




        /// <summary>
        /// 查询方式二
        /// </summary>
        public void SearchXML_Two()
        {
            /*
             * 此种查询方式较第一种更稳定，压力也会更大
             */
            ds = new DataSet();
            ds.ReadXml(x_Path);
            if (ds != null && ds.Tables.Count > 0)
            {
                IEnumerable<DataRow> query = from xm in ds.Tables[0].AsEnumerable()
                                             where xm.Field<String>("x_Name").Contains(key)
                                             orderby xm.Field<String>("x_Age") descending
                                             select xm;
                if (query != null)
                {
                    if (query.Count() > 0)
                    {
                        this.gvXML.DataSource = query.CopyToDataTable();
                        this.gvXML.DataBind();
                    }
                    else
                    {
                        ClientScript.RegisterStartupScript(GetType(),"alert('查询的信息不存在');",true);
                    }
                }
            }
        }


     /// <summary>
        /// 提交信息
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        protected void btnSubmit_Click(object sender,EventArgs e)
        {
            if (!IsEmpty())
            {
                try
                {
                    XElement elements = XElement.Load(x_Path);

                    if (String.IsNullOrEmpty(x_Id))  //新增
                    {
                        XElement new_Child = new XElement("ChildNodes",new XAttribute("x_Id",Guid.NewGuid()),new XElement("x_Name",this.tBox_Name.Text.Trim()),new XElement("x_Gender",this.tBox_Gender.Text.Trim()),new XElement("x_Age",this.tBox_Age.Text.Trim()),new XElement("x_Address",this.tBox_Address.Text.Trim()),new XElement("x_Tel",this.tBox_Tel.Text.Trim()),new XElement("x_Remark",this.tBox_Remark.Text.Trim())
                            );

                        elements.Add(new_Child);
                        elements.Save(x_Path);
                    }
                    else
                    {
                        //修改
                        IEnumerable<XElement> element = from xm in elements.Elements("ChildNodes")
                                                        where xm.Attribute("x_Id").Value.Equals(x_Id)
                                                        select xm;

                        if (element != null && element.Count() > 0)
                        {
                            XElement first = element.First();
                            first.SetElementValue("x_Name",this.tBox_Name.Text.Trim());
                            first.SetElementValue("x_Gender",this.tBox_Gender.Text.Trim());
                            first.SetElementValue("x_Age",this.tBox_Age.Text.Trim());
                            first.SetElementValue("x_Address",this.tBox_Address.Text.Trim());
                            first.SetElementValue("x_Tel",this.tBox_Tel.Text.Trim());
                            first.SetElementValue("x_Remark",this.tBox_Remark.Text.Trim());

                            elements.Save(x_Path);
                        }
                    }

                    ClientScript.RegisterStartupScript(GetType(),"alert('" + (String.IsNullOrEmpty(x_Id) == true ? "添加" : "修改") + "成功！');",true);
                    LoadXML_Two();
                    //隐藏
                    this.dt_Add.Attributes.Add("style","display: none;");

                    //清空
                    Clearn();
                }
                catch (Exception ex)
                {
                    ClientScript.RegisterStartupScript(GetType(),true);
                }
            }
            else
            {
                ClientScript.RegisterStartupScript(GetType(),"alert('输入不为空!');",true);
                this.dt_Add.Attributes.Remove("style");
            }
        }


       /// <summary>
        /// 删除信息
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        protected void gvXML_RowDeleting(object sender,GridViewDeleteEventArgs e)
        {
            String x_Id = this.gvXML.DataKeys[e.RowIndex].Value.ToString().Trim();
            if (!String.IsNullOrEmpty(x_Id))
            {
                XElement elements = XElement.Load(x_Path);
                IEnumerable<XElement> element = from xm in elements.Elements("ChildNodes")
                                                where xm.Attribute("x_Id").Value.Trim().Equals(x_Id)
                                                select xm;

                if (element.Count() > 0)
                {
                    //删除
                    element.First().Remove();
                    elements.Save(x_Path);

                    //重新加载
                    LoadXML_Two();

                    ClientScript.RegisterStartupScript(GetType(),"alert('删除成功成功！');",true);
                }
            }
        }

  
      扩充：
      #region DataSet、查询结果 转化为XML
        /// <summary>
        /// 转化为XML
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        protected void ButnGetXML_Click(object sender,EventArgs e)
        {
            XDocument xdm = new XDocument(
               new XDeclaration("1.0","utf-8","yes"),new XComment("这里声明相关属性"),new XElement("RootNode",new XComment("这是一个父节点"),from es in dc.EA_Script
                   where es.Id <= 150
                   select new XElement[]{  
                       new XElement("ChildNodes",new XComment("这里是子节点"),es.Id),new XElement("x_Title",es.Title),new XElement("x_Url",es.FName),new XElement("x_Detail",es.Detail),new XElement("x_Downloads",es.Downloads),new XElement("x_DateTime",es.DateTime.ToString())
                   )}
               )
            );

            xdm.Save(x_Path);
            ClientScript.RegisterStartupScript(GetType(),"alert('创建XML文件成功！')",true);
        }




        /// <summary>
        /// DataSet数据转化为XML文件
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        protected void btnDSGetXML_Click(object sender,EventArgs e)
        {
            StringBuilder strsql = new StringBuilder();
            strsql.Append("SELECT TOP(88) * FROM [dbo].EA_Script es ORDER BY es.Id DESC");

            con = new sqlConnection(ConnectionString);
            sda = new sqlDataAdapter(strsql.ToString(),con);

            try
            {
                DataSet ds = new DataSet();
                sda.Fill(ds,"DSGetXML");
                ds.WriteXml(x_Path);
            }
            catch (Exception ex)
            {
                ClientScript.RegisterStartupScript(GetType(),"alert('DataSet创建DataSetXML文件失败！\n" + ex.Message + "')",true);
            }
            finally
            {
                sda.Dispose();
                ds.Dispose();
                if (con.State == ConnectionState.Open) con.Close();
            }

            ClientScript.RegisterStartupScript(GetType(),"alert('DataSet创建DataSetXML文件成功！')",true);
        }
        #endregion