linq对xml的增删查改

using System;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;
using System.Collections.Generic;


public partial class _Default : System.Web.UI.Page
{


    protected void Page_Load(object sender, EventArgs e)
    {

        if (!IsPostBack)
        {
            //调用自定义bindDl方法绑定下拉列表
            bindDl();
        }

    }

    protected XElement createGoods(string id, string name, string price)
    {
        //创建XML文件元素
        XElement xeGoods = new XElement("goodsID",
              new XAttribute("ID", id),
              new XElement("goodsName", name),
              new XElement("goodsPrice", price));
        //返回XElement对象
        return xeGoods;
    }

    protected void btnAddxml_Click(object sender, EventArgs e)
    {
        //获取XML文件的路径
        string xmlFilePath = Server.MapPath("goods.xml");
        //加载XML文件
        XElement xe = XElement.Load(xmlFilePath);
        //调用自定义createGoods方法添加商品
        xe.Add(createGoods(txtID.Text, txtName.Text, txtPrice.Text));
        //保存添加后的XML文件
        xe.Save(xmlFilePath);
        RegisterStartupScript("", "<script>alert('添加成功！')</script>");
    }

    protected void bindDl()
    {
        //获取XML文件的
        string xmlFilePath = Server.MapPath("goods.xml");
        //加载XML文件
        XElement xel = XElement.Load(xmlFilePath);
        //查询goodsID
        IEnumerable<XElement> elements = from e in xel.Elements("goodsID")
                                         select e;
        //遍历查询后的结果
        foreach (XElement xe in elements)
        {
            //创建ListItem对象
            ListItem li = new ListItem();
            //设置显示文本
            li.Text = xe.Attribute("ID").Value;
            //设置值
            li.Value = xe.Attribute("ID").Value;
            //将LIstItem对象添加到下拉列表中
            DropDownList1.Items.Add(li);
        }

    }

    protected void bindInfo(string strId)
    {
        //获取XML文件
        string xmlFilePath = Server.MapPath("goods.xml");
        //加载XML文件
        XElement xel = XElement.Load(xmlFilePath);
        //查询指定ID的数据
        IEnumerable<XElement> elements = from e in xel.Elements("goodsID")
                                         where e.Attribute("ID").Value == strId
                                         select e;
        //遍历查询后的结果
        foreach (XElement xe in elements)
        {
            //将商品信息显示在文本框中
            txtSId.Text = xe.Attribute("ID").Value;
            txtSName.Text = xe.Element("goodsName").Value;
            txtSPrice.Text = xe.Element("goodsPrice").Value;


        }
    }

    protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
    {
        //获取当前选择的编号
        string strId = DropDownList1.SelectedValue;
        //调用自定义bindInfo方法显示指定编号的商品信息
        bindInfo(strId);
    }

    protected void btnSet_Click(object sender, EventArgs e)
    {
        //获取XML文件的路径
        string xmlFilePath = Server.MapPath("goods.xml");
        //加载XML文件
        XElement xel = XElement.Load(xmlFilePath);
        //查询指定编号的商品
        IEnumerable<XElement> element = from el in xel.Elements("goodsID")
                                        where el.Attribute("ID").Value == DropDownList1.SelectedValue
                                        select el;
        //获取第一个元素
        XElement result = element.First();
       
        //替换节点中的文本
        result.ReplaceNodes(
            new XElement("goodsName", txtSName.Text),
            new XElement("goodsPrice", txtSPrice.Text)
            );
        //保存XML文件
        xel.Save(xmlFilePath);
    }
}

　　网页上显示xml:

 protected void Page_Load(object sender, EventArgs e)
    {
        //获取XML文件的路径
        string xmlFilePath = Server.MapPath("goods.xml");
        //加载XML文件
        XDocument doc = XDocument.Load(xmlFilePath);        
        //输出XML文件
        Response.Write(doc);
        //设置HTTP MIME类型
        Response.ContentType = "text/xml";
        Response.End();
    }

　　详细代码解释在http://download.csdn.net/detail/yekeyishuo/5037848