c#操作xml(1)

using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Xml;
using System.Text;
public partial class xml : System.Web.UI.Page
{
    XmlDocument xmldoc;
    XmlElement xmlelem;
    XmlNode xmlnode;   
    protected void Page_Load(object sender, EventArgs e)
    {
       // createXmlFile();
        //createXmlFile2();
        //createXmlNode();
        //editXmlFile();
       // removeXmlNode();
        editAttribute();
    }
    /// <summary>
    /// 创建xml文件1
    /// </summary>
    public void createXmlFile()
    {
        xmldoc = new XmlDocument();
        xmlnode = xmldoc.CreateNode(XmlNodeType.XmlDeclaration,"","");
        xmldoc.AppendChild(xmlnode);
        xmlelem=xmldoc.CreateElement("", "Employees","");
        xmldoc.AppendChild(xmlelem);
        for (int i = 0; i < 3; i++)
        {
            XmlNode root = xmldoc.SelectSingleNode("Employees");
            XmlElement xe1 = xmldoc.CreateElement("node");
            xe1.SetAttribute("genre","刘浩");
            xe1.SetAttribute("ISBN", "2-3631-4");
            XmlElement xesub1 = xmldoc.CreateElement("title");
            xesub1.InnerText = "c#高级编程";
            xe1.AppendChild(xesub1);
            XmlElement xesub2 = xmldoc.CreateElement("author");
            xesub2.InnerText = "詹姆斯";
            xe1.AppendChild(xesub2);
            XmlElement xesub3 = xmldoc.CreateElement("price");
            xesub2.InnerText = "58.3";
            xe1.AppendChild(xesub3);
            root.AppendChild(xe1);
            xmldoc.Save(Server.MapPath("data.xml"));
        }
    }
    /// <summary>
    /// 创建xml文件
    /// </summary>
    public void createXmlFile2()
    {
        XmlTextWriter xmlwrite;
        string strfilename;
        strfilename = Server.MapPath("data1.xml");
        xmlwrite = new XmlTextWriter(strfilename, Encoding.Default);
        xmlwrite.Formatting = Formatting.Indented;
        xmlwrite.WriteStartDocument();
        xmlwrite.WriteStartElement("Employees");
        xmlwrite.WriteStartElement("node");
        xmlwrite.WriteStartAttribute("genre","刘洪波");
        xmlwrite.WriteStartAttribute("ISBN"," 2 - 3631 - 4");
        xmlwrite.WriteStartElement("title");
        xmlwrite.WriteString("c#高级编程");
        xmlwrite.WriteEndElement();
        xmlwrite.WriteStartElement("author");
        xmlwrite.WriteString("刘浩");
        xmlwrite.WriteEndElement();
        xmlwrite.WriteStartElement("price");
        xmlwrite.WriteString("53.12");
        xmlwrite.WriteEndElement();
        xmlwrite.WriteEndElement();
        xmlwrite.Close();
    }
    /// <summary>
    /// 增加一个节点
    /// </summary>
    public void createXmlNode()
    {
        xmldoc = new XmlDocument();
        xmldoc.Load(Server.MapPath("data.xml"));
        XmlNode root = xmldoc.SelectSingleNode("Employees");
        XmlElement xe1 = xmldoc.CreateElement("node");
        xe1.SetAttribute("geren","张三");
        xe1.SetAttribute("ISBN", "1-1111-1");

        XmlElement xeSub1 = xmldoc.CreateElement("title");
        xeSub1.InnerText = "sql server2005高级开发指南";
        xe1.AppendChild(xeSub1);

        XmlElement xeSub2 = xmldoc.CreateElement("autoer");
        xeSub1.InnerText = "李伟";
        xe1.AppendChild(xeSub2);

        XmlElement xeSub3 = xmldoc.CreateElement("price");
        xeSub1.InnerText = "87.5";
        xe1.AppendChild(xeSub3);
        root.AppendChild(xe1);
        xmldoc.Save(Server.MapPath("data.xml"));

    }
    /// <summary>
    /// 编辑某个节点的值
    /// </summary>
    public void editXmlFile()
    {
        xmldoc = new XmlDocument();
        xmldoc.Load(Server.MapPath("data.xml"));
        XmlNodeList nodeList = xmldoc.SelectSingleNode("Employees").ChildNodes;
        foreach (XmlNode xn in nodeList)//遍历所有子节点 
        {
            XmlElement xe = (XmlElement)xn;//将子节点类型转换为XmlElement类型 
            if (xe.GetAttribute("genre") == "张三")//如果genre属性值为“张三” 
            {
                xe.SetAttribute("genre", "update张三");//则修改该属性为“update张三” 

                XmlNodeList nls = xe.ChildNodes;//继续获取xe子节点的所有子节点 
                foreach (XmlNode xn1 in nls)//遍历 
                {
                    XmlElement xe2 = (XmlElement)xn1;//转换类型 
                    if (xe2.Name == "author")//如果找到 
                    {
                        xe2.InnerText = "亚胜";//则修改
                    }
                }
            }
        } 


        xmldoc.Save(Server.MapPath("data.xml"));
    }
    /// <summary>
    /// 删除一个节点
    /// </summary>
    public void removeXmlNode()
    {
        xmldoc = new XmlDocument();
        xmldoc.Load(Server.MapPath("data.xml"));
        XmlNode root = xmldoc.SelectSingleNode("Employees");
         
         XmlNodeList nodeList = xmldoc.SelectSingleNode("Employees").ChildNodes;
         for (int i = 0; i < nodeList.Count; i++)
         { 
          XmlElement xe=(XmlElement)nodeList.Item(i);
          if (xe.GetAttribute("genre") == "update张三")
          {
              root.RemoveChild(xe);
              if (i < nodeList.Count) i = i - 1;

          }
         }
         xmldoc.Save(Server.MapPath("data.xml"));
    }
    /// <summary>
    /// 修改结点（添加结点的属性和添加结点的自结点）
    /// </summary>
    public void editAttribute()
    {
        xmldoc = new XmlDocument();
        xmldoc.Load(Server.MapPath("data.xml"));
        XmlNodeList xnl = xmldoc.SelectSingleNode("Employees").ChildNodes;
        foreach (XmlNode xn in xnl)
        {
            XmlElement xml = (XmlElement)xn;
            xml.SetAttribute("test","23433");
            XmlElement xmlSub = xmldoc.CreateElement("flag");
            xmlSub.InnerText = "1";
            xml.AppendChild(xmlSub);
            xml.SetAttribute("price","53.4");

        }
        xmldoc.Save(Server.MapPath("data.xml"));
    }
    /// <summary>
    /// 删除某一节点的属性
    /// </summary>
    public void removeXmlAttribute()
    {
        xmldoc = new XmlDocument();
        xmldoc.Load(Server.MapPath("data.xml"));
        XmlNodeList nodelist = xmldoc.SelectSingleNode("Employees").ChildNodes;
        foreach(XmlNode xln in nodelist)
        {
            XmlElement xe1 = (XmlElement)xln;
            xe1.RemoveAttribute("genre");
            XmlNodeList nls = xe1.ChildNodes;
            foreach (XmlNode xn1 in nls)
            {
                XmlElement xle1 = (XmlElement)xn1;
                if (xle1.Name == "flag")
                {
                    xe1.RemoveChild(xle1);
                }
            }
        }
        xmldoc.Save(Server.MapPath("data.xml"));
    }