C#中对 XML节点进行添加,删除,查找和删除操作

从网上整理所得

XMLDocument来操作XML比较简单,虽然有时效率不是很高。代码如下

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 xn 1 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
}
}

  5、查找某一个节点数据。

  
    
XmlElement root = xmldoc.DocumentElement;

XmlNode node
= root.SelectSingleNode( " //bookstore//book[author=' " + 变量 + " '] " ); // 查找指定节点

本文来自CSDN博客,转载请标明出处:http://blog.csdn.net/fan6662000/archive/2008/11/14/3302290.aspx

你可能感兴趣的:(xml)