using System.Xml;
//初始化一个xml实例XmlDocument xml=new XmlDocument();//导入指定xml文件xml.Load(path);xml.Load(HttpContext.Current.Server.MapPath("~/file/bookstore.xml"));//指定一个节点XmlNode root=xml.SelectSingleNode("/root");//获取节点下所有直接子节点XmlNodeList childlist=root.ChildNodes;//判断该节点下是否有子节点root.HasChildNodes;//获取同名同级节点集合XmlNodeList nodelist=xml.SelectNodes("/Root/News");//生成一个新节点XmlElement node=xml.CreateElement("News");//将节点加到指定节点下，作为其子节点root.AppendChild(node);//将节点加到指定节点下某个子节点前root.InsertBefore(node,root.ChildeNodes[i]);//为指定节点的新建属性并赋值node.SetAttribute("id","11111");//为指定节点添加子节点root.AppendChild(node);//获取指定节点的指定属性值string id=node.Attributes["id"].Value;//获取指定节点中的文本string content=node.InnerText;//保存XML文件string path=Server.MapPath("~/file/bookstore.xml");xml.Save(path);//or use :xml.Save(HttpContext.Current.Server.MapPath("~/file/bookstore.xml"));二、具体实例在C#.net中如何操作XML需要添加的命名空间：using System.Xml;定义几个公共对象：XmlDocument xmldoc ;XmlNode xmlnode ;XmlElement xmlelem ;1，创建到服务器同名目录下的xml文件：方法一：xmldoc = new XmlDocument ( ) ;//加入XML的声明段落,<?xml version="1.0" encoding="gb2312"?>XmlDeclaration xmldecl; xmldecl = xmldoc.CreateXmlDeclaration("1.0","gb2312",null); xmldoc.AppendChild ( xmldecl);//加入一个根元素xmlelem = xmldoc.CreateElement ( "" , "Employees" , "" ) ;xmldoc.AppendChild ( xmlelem ) ;//加入另外一个元素for(int i=1;i<3;i++){XmlNode root=xmldoc.SelectSingleNode("Employees");//查找<Employees>XmlElement xe1=xmldoc.CreateElement("Node");//创建一个<Node>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<Node>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<Employees>节点中}//保存创建好的XML文档xmldoc.Save ( Server.MapPath("data.xml") ) ;//结果：在同名目录下生成了名为data.xml的文件，内容如下，<?xml version="1.0" encoding="gb2312"?><Employees> <Node 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> </Node> <Node 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> </Node></Employees>方法二：XmlTextWriter xmlWriter; string strFilename = Server.MapPath("data1.xml") ; xmlWriter = new XmlTextWriter(strFilename,Encoding.Default);//创建一个xml文档 xmlWriter.Formatting = Formatting.Indented; xmlWriter.WriteStartDocument(); xmlWriter.WriteStartElement("Employees"); xmlWriter.WriteStartElement("Node"); xmlWriter.WriteAttributeString("genre","李赞红"); xmlWriter.WriteAttributeString("ISBN","2-3631-4"); xmlWriter.WriteStartElement("title"); xmlWriter.WriteString("CS从入门到精通"); xmlWriter.WriteEndElement(); xmlWriter.WriteStartElement("author"); xmlWriter.WriteString("候捷"); xmlWriter.WriteEndElement(); xmlWriter.WriteStartElement("price"); xmlWriter.WriteString("58.3"); xmlWriter.WriteEndElement(); xmlWriter.WriteEndElement(); xmlWriter.Close();//结果：<?xml version="1.0" encoding="gb2312"?><Employees> <Node 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> </Node></Employees>2，添加一个结点：XmlDocument xmlDoc=new XmlDocument();xmlDoc.Load(Server.MapPath("data.xml"));XmlNode root=xmlDoc.SelectSingleNode("Employees");//查找<Employees>XmlElement xe1=xmlDoc.CreateElement("Node");//创建一个<Node>节点xe1.SetAttribute("genre","张三");//设置该节点genre属性xe1.SetAttribute("ISBN","1-1111-1");//设置该节点ISBN属性XmlElement xesub1=xmlDoc.CreateElement("title");xesub1.InnerText="C#入门帮助";//设置文本节点xe1.AppendChild(xesub1);//添加到<Node>节点中XmlElement xesub2=xmlDoc.CreateElement("author");xesub2.InnerText="高手";xe1.AppendChild(xesub2);XmlElement xesub3=xmlDoc.CreateElement("price");xesub3.InnerText="158.3";xe1.AppendChild(xesub3);root.AppendChild(xe1);//添加到<Employees>节点中xmlDoc.Save ( Server.MapPath("data.xml") );//结果：在xml原有的内容里添加了一个结点，内容如下，<?xml version="1.0" encoding="gb2312"?><Employees> <Node 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> </Node> <Node 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> </Node> <Node genre="张三" ISBN="1-1111-1"> <title>C#入门帮助</title> <author>高手</author> <price>158.3</price> </Node></Employees>3，修改结点的值（属性和子结点）：XmlDocument xmlDoc=new XmlDocument();xmlDoc.Load( Server.MapPath("data.xml") );XmlNodeList nodeList=xmlDoc.SelectSingleNode("Employees").ChildNodes;//获取Employees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")=="张三")//如果genre属性值为“张三”{xe.SetAttribute("genre","update张三");//则修改该属性为“update张三”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}}}}xmlDoc.Save( Server.MapPath("data.xml") );//保存。//结果：将原来的所有结点的信息都修改了，xml的内容如下，<?xml version="1.0" encoding="gb2312"?><Employees> <Node 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> </Node> <Node 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> </Node> <Node genre="update张三" ISBN="1-1111-1"> <title>C#入门帮助</title> <author>亚胜</author> <price>158.3</price> </Node></Employees>4，修改结点（添加结点的属性和添加结点的自结点）：XmlDocument xmlDoc=new XmlDocument();xmlDoc.Load( Server.MapPath("data.xml") );XmlNodeList nodeList=xmlDoc.SelectSingleNode("Employees").ChildNodes;//获取Employees节点的所有子节点foreach(XmlNode xn in nodeList){XmlElement xe=(XmlElement)xn;xe.SetAttribute("test","111111");XmlElement xesub=xmlDoc.CreateElement("flag");xesub.InnerText="1";xe.AppendChild(xesub);}xmlDoc.Save( Server.MapPath("data.xml") );//结果：每个结点的属性都添加了一个，子结点也添加了一个，内容如下，<?xml version="1.0" encoding="gb2312"?><Employees> <Node genre="李赞红" ISBN="2-3631-4" test="111111"> <title>CS从入门到精通</title> <author>候捷</author> <price>58.3</price> <flag>1</flag> </Node> <Node genre="李赞红" ISBN="2-3631-4" test="111111"> <title>CS从入门到精通</title> <author>候捷</author> <price>58.3</price> <flag>1</flag> </Node> <Node genre="update张三" ISBN="1-1111-1" test="111111"> <title>C#入门帮助</title> <author>亚胜</author> <price>158.3</price> <flag>1</flag> </Node></Employees>5，删除结点中的某一个属性：XmlDocument xmlDoc=new XmlDocument();xmlDoc.Load( Server.MapPath("data.xml") );XmlNodeList xnl=xmlDoc.SelectSingleNode("Employees").ChildNodes;foreach(XmlNode xn in xnl){XmlElement xe=(XmlElement)xn;xe.RemoveAttribute("genre");//删除genre属性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=="flag")//如果找到{xe.RemoveChild(xe2);//则删除}}}xmlDoc.Save( Server.MapPath("data.xml") );//]结果：删除了结点的一个属性和结点的一个子结点，内容如下，<?xml version="1.0" encoding="gb2312"?><Employees> <Node ISBN="2-3631-4" test="111111"> <title>CS从入门到精通</title> <author>候捷</author> <price>58.3</price> </Node> <Node ISBN="2-3631-4" test="111111"> <title>CS从入门到精通</title> <author>候捷</author> <price>58.3</price> </Node> <Node ISBN="1-1111-1" test="111111"> <title>C#入门帮助</title> <author>亚胜</author> <price>158.3</price> </Node></Employees>6，删除结点：XmlDocument xmlDoc=new XmlDocument();xmlDoc.Load( Server.MapPath("data.xml") );XmlNode root=xmlDoc.SelectSingleNode("Employees");XmlNodeList xnl=xmlDoc.SelectSingleNode("Employees").ChildNodes;for(int i=0;i<xnl.Count;i++){XmlElement xe=(XmlElement)xnl.Item(i);if(xe.GetAttribute("genre")=="张三"){root.RemoveChild(xe);if(i<xnl.Count)i=i-1;}}xmlDoc.Save( Server.MapPath("data.xml") );//]结果：删除了符合条件的所有结点，原来的内容：<?xml version="1.0" encoding="gb2312"?><Employees> <Node 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> </Node> <Node 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> </Node> <Node genre="张三" ISBN="1-1111-1"> <title>C#入门帮助</title> <author>高手</author> <price>158.3</price> </Node> <Node genre="张三" ISBN="1-1111-1"> <title>C#入门帮助</title> <author>高手</author> <price>158.3</price> </Node></Employees>删除后的内容：<?xml version="1.0" encoding="gb2312"?><Employees> <Node 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> </Node> <Node 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> </Node></Employees> 7，按照文本文件读取xmlSystem.IO.StreamReader myFile =newSystem.IO.StreamReader(Server.MapPath("data.xml"),System.Text.Encoding.Default);//注意System.Text.Encoding.Defaultstring myString = myFile.ReadToEnd();//myString是读出的字符串myFile.Close();三、高级应用/*读取xml数据 两种xml方式*/<aaa> <bb>something</bb> <cc>something</cc></aaa> <aaa> <add key="123" value="321"/></aaa>/*第一种方法*/DS.ReadXml("your xmlfile name");Container.DataItem("bb");Container.DataItem("cc");DS.ReadXmlSchema("your xmlfile name"); /*第二种方法*/<aaa> <add key="123" value="321"/></aaa>如果我要找到123然后取到321应该怎么写呢？ using System.XML;XmlDataDocument xmlDoc = new System.Xml.XmlDataDocument();xmlDoc.Load(@"c:/Config.xml");XmlElement elem = xmlDoc.GetElementById("add");string str = elem.Attributes["value"].Value /*第三种方法: SelectSingleNode 读取两种格式的xml *---/--------------------------------------------------------------------<?xml version="1.0" encoding="utf-8" ?><configuration> <appSettings> <ConnectionString>Data Source=yf; user id=ctm_dbo;password=123</ConnectionString> </appSettings></configuration>--------------------------------------------------------------------------XmlDocument doc = new XmlDocument();doc.Load(strXmlName); XmlNode node=doc.SelectSingleNode("/configuration/appSettings/ConnectionString"); if(node!=null) { string k1=node.Value; //null string k2=node.InnerText;//Data Source=yf; user id=ctm_dbo;password=123 string k3=node.InnerXml;//Data Source=yf; user id=ctm_dbo;password=123 node=null; } ********************************************************************<?xml version="1.0" encoding="utf-8" ?><configuration> <appSettings> <add key="ConnectionString" value="Data Source=yf; user id=ctm_dbo;password=123" /> </appSettings></configuration>**--------------------------------------------------------------------** XmlNode node=doc.SelectSingleNode("/configuration/appSettings/add"); if(node!=null) { string k=node.Attributes["key"].Value; string v=node.Attributes["value"].Value; node=null; }*--------------------------------------------------------------------* XmlNode node=doc.SelectSingleNode("/configuration/appSettings/add"); if(node!=null) { XmlNodeReader nr=new XmlNodeReader(node); nr.MoveToContent(); //检查当前节点是否是内容节点。如果此节点不是内容节点，则读取器向前跳至下一个内容节点或文件结尾。 nr.MoveToAttribute("value"); string s=nr.Value; node=null; }
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