(轉)C#操作xml文件入门實例

ゝ一纸荒年。 2022-08-25 02:08 168阅读 0赞

C\#操作xml文件入门實例

已知有一个XML文件（bookstore.xml）如下：

1、往<bookstore>节点中插入一个<book>节点：

![None.gif][] XmlDocument xmlDoc = new  XmlDocument();  
![None.gif][]xmlDoc.Load( " bookstore.xml " );  
![None.gif][]XmlNode root = xmlDoc.SelectSingleNode( " bookstore " ); // 查找<bookstore>   
![None.gif][] XmlElement xe1 = xmlDoc.CreateElement( " book " ); // 创建一个<book>节点   
![None.gif][] xe1.SetAttribute( " genre " , " 李赞红 " ); // 设置该节点genre属性   
![None.gif][] xe1.SetAttribute( " ISBN " , " 2-3631-4 " ); // 设置该节点ISBN属性   
![None.gif][]   
![None.gif][]XmlElement xesub1 = xmlDoc.CreateElement( " title " );  
![None.gif][]xesub1.InnerText = " CS从入门到精通 " ; // 设置文本节点   
![None.gif][] xe1.AppendChild(xesub1); // 添加到<book>节点中   
![None.gif][] XmlElement xesub2 = xmlDoc.CreateElement( " author " );  
![None.gif][]xesub2.InnerText = " 候捷 " ;  
![None.gif][]xe1.AppendChild(xesub2);  
![None.gif][]XmlElement xesub3 = xmlDoc.CreateElement( " price " );  
![None.gif][]xesub3.InnerText = " 58.3 " ;  
![None.gif][]xe1.AppendChild(xesub3);  
![None.gif][]  
![None.gif][]root.AppendChild(xe1); // 添加到<bookstore>节点中   
![None.gif][] xmlDoc.Save( " bookstore.xml " );  
![None.gif][]  
![None.gif][]

//================  
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”。

![None.gif][] XmlNodeList nodeList = xmlDoc.SelectSingleNode( " bookstore " ).ChildNodes; // 获取bookstore节点的所有子节点   
![None.gif][] foreach (XmlNode xn  in  nodeList) // 遍历所有子节点   
![ExpandedBlockStart.gif][]![ContractedBlock.gif][] ... \{  
![InBlock.gif][]XmlElement xe=(XmlElement)xn;//将子节点类型转换为XmlElement类型  
![InBlock.gif][]if(xe.GetAttribute("genre")=="李赞红")//如果genre属性值为“李赞红”  
![ExpandedSubBlockStart.gif][]![ContractedSubBlock.gif][]...\{  
![InBlock.gif][]xe.SetAttribute("genre","update李赞红");//则修改该属性为“update李赞红”  
![InBlock.gif][]  
![InBlock.gif][]XmlNodeList nls=xe.ChildNodes;//继续获取xe子节点的所有子节点  
![InBlock.gif][]foreach(XmlNode xn1 in nls)//遍历  
![ExpandedSubBlockStart.gif][]![ContractedSubBlock.gif][]...\{  
![InBlock.gif][]XmlElement xe2=(XmlElement)xn1;//转换类型  
![InBlock.gif][]if(xe2.Name=="author")//如果找到  
![ExpandedSubBlockStart.gif][]![ContractedSubBlock.gif][]...\{  
![InBlock.gif][]xe2.InnerText="亚胜";//则修改  
![InBlock.gif][]break;//找到退出来就可以了  
![ExpandedSubBlockEnd.gif][]\}  
![ExpandedSubBlockEnd.gif][]\}  
![InBlock.gif][]break;  
![ExpandedSubBlockEnd.gif][]\}  
![ExpandedBlockEnd.gif][]\}   
![None.gif][]  
![None.gif][]xmlDoc.Save( " bookstore.xml " ); // 保存。  
![None.gif][]

//=================

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。

![None.gif][] XmlNodeList xnl = xmlDoc.SelectSingleNode( " bookstore " ).ChildNodes;  
![None.gif][]  
![None.gif][] foreach (XmlNode xn  in  xnl)  
![ExpandedBlockStart.gif][]![ContractedBlock.gif][] ... \{  
![InBlock.gif][]XmlElement xe=(XmlElement)xn;  
![InBlock.gif][]  
![InBlock.gif][]  
![InBlock.gif][]if(xe.GetAttribute("genre")=="fantasy")  
![ExpandedSubBlockStart.gif][]![ContractedSubBlock.gif][]...\{  
![InBlock.gif][]xe.RemoveAttribute("genre");//删除genre属性  
![ExpandedSubBlockEnd.gif][]\}  
![InBlock.gif][]elseif(xe.GetAttribute("genre")=="update李赞红")  
![ExpandedSubBlockStart.gif][]![ContractedSubBlock.gif][]...\{  
![InBlock.gif][]xe.RemoveAll();//删除该节点的全部内容  
![ExpandedSubBlockEnd.gif][]\}  
![ExpandedBlockEnd.gif][]\}   
![None.gif][]xmlDoc.Save( " bookstore.xml " );  
![None.gif][]  
![None.gif][]

//====================

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。

![None.gif][] XmlNode xn = xmlDoc.SelectSingleNode( " bookstore " );  
![None.gif][]  
![None.gif][]XmlNodeList xnl = xn.ChildNodes;  
![None.gif][]  
![None.gif][] foreach (XmlNode xnf  in  xnl)  
![ExpandedBlockStart.gif][]![ContractedBlock.gif][] ... \{  
![InBlock.gif][]XmlElement xe=(XmlElement)xnf;  
![InBlock.gif][]Console.WriteLine(xe.GetAttribute("genre"));//显示属性值  
![InBlock.gif][]Console.WriteLine(xe.GetAttribute("ISBN"));  
![InBlock.gif][]  
![InBlock.gif][]XmlNodeList xnf1=xe.ChildNodes;  
![InBlock.gif][]foreach(XmlNode xn2 in xnf1)  
![ExpandedSubBlockStart.gif][]![ContractedSubBlock.gif][]...\{  
![InBlock.gif][]Console.WriteLine(xn2.InnerText);//显示子节点点文本  
![ExpandedSubBlockEnd.gif][]\}  
![ExpandedBlockEnd.gif][]\}   
![None.gif][]

本文轉自: [http://www.knowsky.com/340889.html][http_www.knowsky.com_340889.html]

[None.gif]: /images/20220824/b0f79b4d1ef84794ba94abcb0a92a8dd.png
[ExpandedBlockStart.gif]: http://images.csdn.net/syntaxhighlighting/OutliningIndicators/ExpandedBlockStart.gif
[ContractedBlock.gif]: /images/20220824/11ad281d6c5048a990c3392a4fe782d7.png
[InBlock.gif]: /images/20220824/8275c33d29d2479cb6f9ac477563921f.png
[ExpandedSubBlockStart.gif]: http://images.csdn.net/syntaxhighlighting/OutliningIndicators/ExpandedSubBlockStart.gif
[ContractedSubBlock.gif]: /images/20220824/629e5ad1fb754257869b97d43558edfc.png
[ExpandedSubBlockEnd.gif]: /images/20220824/690c3a8362e64ba685ff7dd19159de64.png
[ExpandedBlockEnd.gif]: /images/20220824/5a2876847e8c403b9d2238faa7e60cef.png
[http_www.knowsky.com_340889.html]: http://www.knowsky.com/340889.html