C# 里XML文件读写
已知有一个XML文件（bookstore.xml）如下：<?xml version="1.0" encoding="gb2312"?><bookstore><book genre="fantasy" ISBN="2-3631-4"><title>Oberon's Legacy</title><author>Corets, Eva</author><price>5.95</price></book></bookstore> 1、往<bookstore>节点中插入一个<book>节点：XmlDocument xmlDoc=new XmlDocument();xmlDoc.Load("bookstore.xml");XmlNode root=xmlDoc.SelectSingleNode("bookstore");//查找<bookstore>XmlElement xe1=xmlDoc.CreateElement("book");//创建一个<book>节点xe1.SetAttribute("genre","李赞红");//设置该节点genre属性xe1.SetAttribute("ISBN","2-3631-4");//设置该节点ISBN属性XmlElement xesub1=xmlDoc.CreateElement("title");xesub1.InnerText="CS从入门到精通";//设置文本节点xe1.AppendChild(xesub1);//添加到<book>节点中XmlElement xesub2=xmlDoc.CreateElement("author");xesub2.InnerText="候捷";xe1.AppendChild(xesub2);XmlElement xesub3=xmlDoc.CreateElement("price");xesub3.InnerText="58.3";xe1.AppendChild(xesub3);root.AppendChild(xe1);//添加到<bookstore>节点中xmlDoc.Save("bookstore.xml");//================结果为：<?xml version="1.0" encoding="gb2312"?><bookstore><book genre="fantasy" ISBN="2-3631-4"><title>Oberon's Legacy</title><author>Corets, Eva</author><price>5.95</price></book><book genre="李赞红" ISBN="2-3631-4"><title>CS从入门到精通</title><author>候捷</author><price>58.3</price></book></bookstore>2、修改节点：将genre属性值为“李赞红“的节点的genre值改为“update李赞红”，将该节点的子节点<author>的文本修改为“亚胜”。XmlNodeList nodeList=xmlDoc.SelectSingleNode("bookstore").ChildNodes;//获取bookstore节点的所有子节点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")=="李赞红")//如果genre属性值为“李赞红”
{ xe.SetAttribute("genre","update李赞红");//则修改该属性为“update李赞红”
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break;//找到退出来就可以了
} }break;
} }xmlDoc.Save("bookstore.xml");//保存。//=================最后结果为：<?xml version="1.0" encoding="gb2312"?><bookstore><book genre="fantasy" ISBN="2-3631-4"><title>Oberon's Legacy</title><author>Corets, Eva</author><price>5.95</price></book><book genre="update李赞红" ISBN="2-3631-4"><title>CS从入门到精通</title><author>亚胜</author><price>58.3</price></book></bookstore>3、删除 <book genre="fantasy" ISBN="2-3631-4">节点的genre属性，删除 <book genre="update李赞红" ISBN="2-3631-4">节点。XmlNodeList xnl=xmlDoc.SelectSingleNode("bookstore").ChildNodes;foreach(XmlNode xn in xnl){ XmlElement xe=(XmlElement)xn;if(xe.GetAttribute("genre")=="fantasy"){ xe.RemoveAttribute("genre");//删除genre属性} else if(xe.GetAttribute("genre")=="update李赞红"){ xe.RemoveAll();//删除该节点的全部内容} }xmlDoc.Save("bookstore.xml");//====================最后结果为：<?xml version="1.0" encoding="gb2312"?><bookstore><book ISBN="2-3631-4"><title>Oberon's Legacy</title><author>Corets, Eva</author><price>5.95</price></book><book></book></bookstore> 4、显示所有数据。XmlNode xn=xmlDoc.SelectSingleNode("bookstore");XmlNodeList xnl=xn.ChildNodes;foreach(XmlNode xnf in xnl){ XmlElement xe=(XmlElement)xnf;Console.WriteLine(xe.GetAttribute("genre"));//显示属性值Console.WriteLine(xe.GetAttribute("ISBN"));XmlNodeList xnf1=xe.ChildNodes;foreach(XmlNode xn2 in xnf1){ Console.WriteLine(xn2.InnerText);//显示子节点点文本} } 另有：using System;using System.IO;using System.Web;using System.Text;using System.Xml;using System.Collections;namespace ShopWeb.Class{ /// <summary>/// Log 的摘要说明。/// </summary>public class Log{ private XmlDocument xmlLog=new XmlDocument(); private HttpContext context=HttpContext.Current; private string xmlPath=""; /// <summary> /// 构造函数 /// </summary> /// <param name="XmlPath"></param> public Log(string XmlPath) { xmlPath=XmlPath; xmlLog.Load(context.Server.MapPath(XmlPath)); } /// <summary> /// 增加一个节点，该节点由子节点构成 /// </summary> /// <param name="HTChilds"></param> /// <param name="ParentName"></param> /// <returns></returns> public bool AddNodeByChild(Hashtable HTChilds ,string ParentName) { try { XmlNode Parent=xmlLog.CreateElement(ParentName); XmlNode Child; IDictionaryEnumerator myEnumerator=HTChilds.GetEnumerator(); while(myEnumerator.MoveNext()) { Child=xmlLog.CreateElement(myEnumerator.Key.ToString()); Child.InnerText=myEnumerator.Value.ToString(); Parent.AppendChild(Child); xmlLog.DocumentElement.AppendChild(Parent); } xmlLog.Save(context.Server.MapPath(xmlPath)); return true; } catch { return false; } } /// <summary> /// 增加一个节点 该节点由属性构成 /// </summary> /// <param name="htAttributes"></param> /// <param name="NodeName"></param> /// <returns></returns> public bool AddNodeByAttribute(Hashtable htAttributes,string NodeName) { try { XmlNode AddNode=xmlLog.CreateElement(NodeName); IDictionaryEnumerator myEnumerator=htAttributes.GetEnumerator(); XmlAttribute atr; while(myEnumerator.MoveNext()) { atr=xmlLog.CreateAttribute(myEnumerator.Key.ToString()); atr.InnerText=myEnumerator.Value.ToString(); AddNode.Attributes.Append(atr); xmlLog.DocumentElement.AppendChild(AddNode); } xmlLog.Save(context.Server.MapPath(xmlPath)); return true; } catch { return false; } } /// <summary> /// 或得指定查询节点得子节点数目 /// </summary> /// <param name="QueryPath"></param> /// <returns></returns> public int ChildCount(string QueryPath) { try { XmlNode ResultNodes=xmlLog.SelectSingleNode(QueryPath); return ResultNodes.ChildNodes.Count; } catch { return -1; } } /// <summary> /// 删除指定路径的节点 /// </summary> /// <param name="QueryPath"></param> /// <returns></returns> public bool DelelteNode(string QueryPath) { try { XmlNodeList ResultNodes=xmlLog.SelectNodes(QueryPath); for(int i=0;i<ResultNodes.Count;i++) { XmlNode ParentNode=ResultNodes.ParentNode; ParentNode.RemoveChild(ResultNodes); } xmlLog.Save(context.Server.MapPath(xmlPath)); return true; } catch { return false; } } /// <summary> /// 查询节点 /// </summary> /// <param name="QueryPath"></param> /// <returns></returns> public XmlNodeList QueryNode(string QueryPath) { try { XmlNodeList ResultNodes=xmlLog.SelectNodes(QueryPath); return ResultNodes; } catch { return null; } }}}
