C#操作XML

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Xml;

namespace PuTianCheng
{
    /// <summary>
    /// XmlHelper 的摘要说明
    /// </summary>
    public class XmlHelper
    {
        public XmlHelper()
        {
        }

        /// <summary>
        /// 读取数据
        /// </summary>
        /// <param name="path">路径</param>
        /// <param name="node">节点</param>
        /// <param name="attribute">属性名，非空时返回该属性值，否则返回串联值</param>
        /// <returns>string</returns>
        /**************************************************
         * 使用示列:
         * XmlHelper.Read(path, "/Node", "")
         * XmlHelper.Read(path, "/Node/Element[@Attribute='Name']", "Attribute")
         ************************************************/
        public static string Read(string path, string node, string attribute)
        {
            string value = "";
            try
            {
                XmlDocument doc = new XmlDocument();
                doc.Load(path);
                XmlNode xn = doc.SelectSingleNode(node);
                value = (attribute.Equals("") ? xn.InnerText : xn.Attributes[attribute].Value);
            }
            catch { }
            return value;
        }

        /// <summary>
        /// 插入数据
        /// </summary>
        /// <param name="path">路径</param>
        /// <param name="node">节点</param>
        /// <param name="element">元素名，非空时插入新元素，否则在该元素中插入属性</param>
        /// <param name="attribute">属性名，非空时插入该元素属性值，否则插入元素值</param>
        /// <param name="value">值</param>
        /// <returns></returns>
        /**************************************************
         * 使用示列:
         * XmlHelper.Insert(path, "/Node", "Element", "", "Value")
         * XmlHelper.Insert(path, "/Node", "Element", "Attribute", "Value")
         * XmlHelper.Insert(path, "/Node", "", "Attribute", "Value")
         ************************************************/
        public static void Insert(string path, string node, string element, string attribute, string value)
        {
            try
            {
                XmlDocument doc = new XmlDocument();
                doc.Load(path);
                XmlNode xn = doc.SelectSingleNode(node);
                if (element.Equals(""))
                {
                    if (!attribute.Equals(""))
                    {
                        XmlElement xe = (XmlElement)xn;
                        xe.SetAttribute(attribute, value);
                    }
                }
                else
                {
                    XmlElement xe = doc.CreateElement(element);
                    if (attribute.Equals(""))
                        xe.InnerText = value;
                    else
                        xe.SetAttribute(attribute, value);
                    xn.AppendChild(xe);
                }
                doc.Save(path);
            }
            catch { }
        }

        /// <summary>
        /// 修改数据
        /// </summary>
        /// <param name="path">路径</param>
        /// <param name="node">节点</param>
        /// <param name="attribute">属性名，非空时修改该节点属性值，否则修改节点值</param>
        /// <param name="value">值</param>
        /// <returns></returns>
        /**************************************************
         * 使用示列:
         * XmlHelper.Insert(path, "/Node", "", "Value")
         * XmlHelper.Insert(path, "/Node", "Attribute", "Value")
         ************************************************/
        public static void Update(string path, string node, string attribute, string value)
        {
            try
            {
                XmlDocument doc = new XmlDocument();
                doc.Load(path);
                XmlNode xn = doc.SelectSingleNode(node);
                XmlElement xe = (XmlElement)xn;
                if (attribute.Equals(""))
                    xe.InnerText = value;
                else
                    xe.SetAttribute(attribute, value);
                doc.Save(path);
            }
            catch { }
        }

        /// <summary>
        /// 删除数据
        /// </summary>
        /// <param name="path">路径</param>
        /// <param name="node">节点</param>
        /// <param name="attribute">属性名，非空时删除该节点属性值，否则删除节点值</param>
        /// <param name="value">值</param>
        /// <returns></returns>
        /**************************************************
         * 使用示列:
         * XmlHelper.Delete(path, "/Node", "")
         * XmlHelper.Delete(path, "/Node", "Attribute")
         ************************************************/
        public static void Delete(string path, string node, string attribute)
        {
            try
            {
                XmlDocument doc = new XmlDocument();
                doc.Load(path);
                XmlNode xn = doc.SelectSingleNode(node);
                XmlElement xe = (XmlElement)xn;
                if (attribute.Equals(""))
                    xn.ParentNode.RemoveChild(xn);
                else
                    xe.RemoveAttribute(attribute);
                doc.Save(path);
            }
            catch { }
        }
    }
}

使用示例：
//string xml = Server.MapPath("XmlFile.xml");
            string xml = @"d:\我的文档\Visual Studio 2008\Projects\ConsoleApplication1\ConsoleApplication1\XmlFile.xml";
            //插入元素
            XmlHelper.Insert(xml, "/Root", "Studio", "", "");
            //插入元素/属性
            //XmlHelper.Insert(xml, "/Root/Studio", "Site", "Name", "小路工作室");
            //XmlHelper.Insert(xml, "/Root/Studio", "Site", "Name", "丁香鱼工作室");
            //XmlHelper.Insert(xml, "/Root/Studio", "Site", "Name", "谱天城工作室");
            //XmlHelper.Insert(xml, "/Root/Studio/Site[@Name='谱天城工作室']", "Master", "", "红尘静思");
            //插入属性
            //XmlHelper.Insert(xml, "/Root/Studio/Site[@Name='小路工作室']", "", "Url", "http://www.wzlu.com/");
            //XmlHelper.Insert(xml, "/Root/Studio/Site[@Name='丁香鱼工作室']", "", "Url", "http://www.luckfish.net/");
            //XmlHelper.Insert(xml, "/Root/Studio/Site[@Name='谱天城工作室']", "", "Url", "http://www.putiancheng.com/");
            //修改元素值
            //XmlHelper.Update(xml, "/Root/Studio/Site[@Name='谱天城工作室']/Master", "", "RedDust");
            //修改属性值
            //XmlHelper.Update(xml, "/Root/Studio/Site[@Name='谱天城工作室']", "Url", "http://www.putiancheng.net/");
            //XmlHelper.Update(xml, "/Root/Studio/Site[@Name='谱天城工作室']", "Name", "PuTianCheng Studio");
            //读取元素值
            Console.Write("<div>" + XmlHelper.Read(xml, "/Root/Studio/Site/Master", "") + "</div>");
            //读取属性值
            Console.Write("<div>" + XmlHelper.Read(xml, "/Root/Studio/Site", "Url") + "</div>");
            //读取特定属性值
            Console.Write("<div>" + XmlHelper.Read(xml, "/Root/Studio/Site[@Name='丁香鱼工作室']", "Url") + "</div>");
            //删除属性
            //XmlHelper.Delete(xml, "/Root/Studio/Site[@Name='小路工作室']", "Url");
            //删除元素
            //XmlHelper.Delete(xml, "/Root/Studio", "");

XMLFile.xml文件：
<?xml version="1.0" encoding="utf-8"?>
<Root/>