C#读写xml
C#读写xml
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;
}
}
}
}