xml是一种可扩展标记语言，在电子计算机中，标记指计算机所能理解的信息符号，通过此种标记，计算机之间可以处理包含各种的信息比如文章等。它可以用来标记数据、定义数据类型，是一种允许用户对自己的标记语言进行定义的源语言。 它非常适合万维网传输，提供统一的方法来描述和交换独立于应用程序或供应商的结构化数据。是Internet环境中跨平台的、依赖于内容的技术，也是当今处理分布式结构信息的有效工具。
现在演示一下在asp.net里如何操作读写xml文件
1.新建一个web窗体WebForm1.aspx和一个xml文件XMLFile1.xml
(1)WebForm1.aspx页面代码
放置两个按钮，一个用来写入，一个用来读取；和一个lable控件用来显示读取信息
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="WebForm1.aspx.cs" Inherits="读写xml文件.WebForm1" %><!DOCTYPE html><html xmlns="http://www.w3.org/1999/xhtml"><head runat="server"><meta http-equiv="Content-Type" content="text/html; charset=utf-8"/> ???<title></title></head><body> ???<form id="form1" runat="server"> ???????<div> ???????????<asp:Button ID="Button1" runat="server" Text="写入" OnClick="Button1_Click" /> ???????????<asp:Button ID="write" runat="server" Text="读取" OnClick="write_Click" /> ???????</div> ???????<asp:Label ID="Label1" runat="server"></asp:Label> ???</form></body></html>
(2)WebForm1.aspx.cs后台代码
using System;using System.Collections.Generic;using System.Linq;using System.Web;using System.Web.UI;using System.Web.UI.WebControls;using System.Xml;namespace 读写xml文件{ ???public partial class WebForm1 : System.Web.UI.Page ???{ ???????protected void Page_Load(object sender, EventArgs e) ???????{ ???????} ???????protected void Button1_Click(object sender, EventArgs e) ???????{ //写入xml ?????????//写入xml的路径 ???????????string path = Server.MapPath("XMLFile1.xml"); ???????????//创建文件格式对象 ???????????XmlTextWriter xml = new XmlTextWriter(path, System.Text.Encoding.UTF8); ???????????xml.WriteStartDocument();//调用WriteStartDocument()方法来开始写入XML文档 ???????????????????????????????????????????????xml.WriteStartElement("最美评比"); //写根节点 ???????????xml.WriteStartElement("student");//写子节点 ???????????xml.WriteStartElement("张三");//写字节点 ???????????xml.WriteAttributeString("color", "red");//给节点添加属性（好像无用） ???????????xml.WriteString("姓名：张三"); ???????????xml.WriteString("<br />备注：I‘m a boy"); ?//给节点内部添加文本 ???????????xml.WriteEndElement();//关闭字节点 ???????????xml.WriteEndElement();//关闭子节点 ???????????xml.WriteStartElement("student"); ???????????//通过WriteElementString可以添加一个字节点同时添加节点内容 ???????????xml.WriteElementString("姓名", "貂蝉"); ???????????xml.WriteElementString("备注", "I‘m a gril"); ???????????xml.WriteEndElement(); ???????????xml.WriteStartElement("student"); ???????????xml.WriteElementString("姓名", "吕布"); ???????????xml.WriteElementString("备注", "I‘m a MR"); ???????????xml.WriteEndElement(); ???????????????????????//相比上方先建节点，在添加节点内容，这种方法更简便 ???????????xml.WriteStartElement("student"); ???????????xml.WriteElementString("stuNO", "1002"); ???????????xml.WriteElementString("stuName", "cv"); ???????????//student标签的关闭标签 ???????????xml.WriteEndElement(); ???????????xml.WriteEndElement();//关闭根节点 ???????????xml.Flush();//刷新流 ???????????xml.Close();//关闭流 ???????} ???????protected void write_Click(object sender, EventArgs e) ???????{//读取 ???????????string path = Server.MapPath("XMLFile1.xml");//读取路径 ???????????//创建文件格式对象 ???????????XmlTextReader xml = new XmlTextReader(path);//调用路径 ???????????int index = 1;//索引值学生 ???????????int a = 1; ???????????while (xml.Read()) ???????????{ ???????????????if (xml.NodeType == XmlNodeType.Element) ???????????????{ ???????????????????if (xml.Name == "student") ???????????????????{ ???????????????????????this.Label1.Text += "学生 " + index + " 信息如下：<br />"; ???????????????????????index++; ???????????????????} ???????????????????if (xml.Name == "stuNO") ???????????????????{ ???????????????????????this.Label1.Text += "学号：" + xml.ReadElementString() + "<br />"; ???????????????????} ???????????????????if (xml.Name == "stuName") ???????????????????{ ???????????????????????this.Label1.Text += "姓名：" + xml.ReadElementString() + "<br />"; ???????????????????} ???????????????????if (xml.Name == "姓名") ???????????????????{ ???????????????????????this.Label1.Text += "姓名：" + xml.ReadElementString() + "<br />"; ??????????????????????????????????????????} ???????????????????if (xml.Name == "备注")//括号里为节点名 ???????????????????{ ???????????????????????this.Label1.Text += "备注：" + xml.ReadElementString() + "<br />"; ???????????????????} ???????????????????if (xml.Name == "张三")//括号里为节点名 ???????????????????{ ???????????????????????this.Label1.Text += "" + xml.ReadElementString() + "<br />"; ???????????????????} ???????????????} ???????????} ???????} ???}}值得注意的是，在后台代码里每一个节点的WriteStartElement要对应一个WriteEndElement；层次关系要分明，尽管在你写入的时候没报错，但是在你读取的时候，可能会发生不是你想要的结果
(3)XMLFile1.xml
新建的xml文件除了顶头文件表示，其余都是空白的
（4）运行程序
注意的是：你首先要把数据提交写入到xml文件里，才能读取到数据
点击提交按钮之后，不要急着去点读取按钮，返回程序会有这样一个界面
点击是，更新xml里的数据
以下就是更新之后的XMLFile1.xml文件
1 <?xml version="1.0" encoding="utf-8"?> 2 <最美评比> 3 ??<student> 4 ????<张三 color="red">姓名：张三<br />备注：I‘m a boy</张三> 5 ??</student> 6 ??<student> 7 ????<姓名>貂蝉</姓名> 8 ??<备注>I‘m a gril</备注> 9 ??</student>10 ??<student>11 ????<姓名>吕布</姓名>12 ????<备注>I‘m a MR</备注>13 ??</student>14 ??<student>15 ????<stuNO>1002</stuNO>16 ????<stuName>cv</stuName>17 ??</student>18 </最美评比>
关灯之后写完的累趴小编！！
ASP.NET写入和读取xml文件
原文地址：https://www.cnblogs.com/kalezhangtao/p/9053882.html