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;

}

}

}

}