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C#写入xml文件
1、XmlDocument
1。我认为是最原始,最基本的一种:利用XmlDocument向一个XML文件里写节点,然后再利用XmlDocument保存文件。
首先加载要写入的XML文件,但是如果没有的,就要新建,在新建的过程中,要有写入的代码;
XmlDocument doc = new XmlDocument(); try { doc.Load("new.xml"); } catch { XmlTextWriter xtw = new XmlTextWriter("new.xml", Encoding.UTF8); //新建XML文件 xtw.WriteStartDocument(); xtw.WriteStartElement("gnode"); // gnode根节点 xtw.WriteStartElement("myxm1"); // gnode根节点下的元素myxmls xtw.WriteEndElement(); xtw.WriteEndElement(); xtw.WriteEndDocument(); xtw.Close(); doc.Load("new.xml"); } XmlNode xn = doc.DocumentElement; //找到根节点 XmlElement xe = doc.CreateElement("myxml2"); //在根节点下创建元素,如果是属性,则用XmlAttribute; xe.InnerText = "薪薪代码hahaha"; //给子节点写入文本节点(值) xn.AppendChild(xe); //根节点将其纳入 doc.Save("new2.xml"); //利用XmlDocument保存文件 }
注意点:在新建根节点的时候,WriteStartElement,只能嵌套,也就是只能有一个根节点。
2、DataSet对象里的值来生成XML文件
应用到数据库,将数据库的DataSet对象里的值来生成XML文件的元素;
using (SqlConnection con = new SqlConnection("Server=.;DataBase=HGSTUDY;uid=sa;pwd=yao")) { con.Open(); SqlCommand command = new SqlCommand("select * from GL_STUDY", con); command.CommandType = CommandType.Text; DataSet ds = new DataSet("DATASET"); //DATASET将成为XML文件中的根节点名称,否则系统将其命名为NewDataSet SqlDataAdapter sda = new SqlDataAdapter(); sda.SelectCommand = command; sda.Fill(ds, "DATATABLE"); //DATATABLE为所生成XML文件中的子节点名称,否则系统将其命名为Table。 ds.WriteXml("dbxml.xml"); // DataSet的方法WriteXml将数据写入到XML文件,就是这么一句话。如果不保存到文件,直接ds.GetXML() }
3、利用XmlSerializer来将类的属性值转换为XML文件的元素值。
用一个字符串作为一个XML文档中的xmlAttribute或xmlElement。[其元素或属性由类的定义来设置(xml串行化)]
using System;System.xml.Serialization;
先初始化一个类,设置属性值
var xmlDoc = new XmlDocument();//Create the xml declaration firstxmlDoc.AppendChild(xmlDoc.CreateXmlDeclaration("1.0", "utf-8", null));//Create the root node and append into docvar el = xmlDoc.CreateElement("Contacts");xmlDoc.AppendChild(el);// ContactXmlElement elementContact = xmlDoc.CreateElement("Contact");XmlAttribute attrID = xmlDoc.CreateAttribute("id");attrID.Value = "01";elementContact.Attributes.Append(attrID);el.AppendChild(elementContact);// Contact NameXmlElement elementName = xmlDoc.CreateElement("Name");elementName.InnerText = "Daisy Abbey";elementContact.AppendChild(elementName);// Contact GenderXmlElement elementGender = xmlDoc.CreateElement("Gender");elementGender.InnerText = "female";elementContact.AppendChild(elementGender);xmlDoc.Save("test1.xml");
建XmlSerializer实例
class XXX { XmlSerializer ser = new XmlSerializer(Type.GetType("forxml.truck")); Truck tr = new Truck(); tr.ID = 1; tr.cheID = "赣A T34923"; }
Serialize方法–完成对类的串行化
XmlTextWriter xtw = new XmlTextWriter("myxml.xml",Encoding.UTF8); 用XmlTextWriter 创建一个XML文件 ser.Serialize(xtw, tr); //如果只想显示,可以直接ser.Serialize(Console.Out, tr);}
xml常用方法:
定义xml文档:XmlDocument xmlDoc = new XmlDocument();
初始化xml文档:xmlDoc.Load(“D:\book.xml”);//找到xml文件
创建根元素:XmlElement xmlElement = xmlDoc.CreateElement(“”, “Employees”, “”);
创建节点:XmlElement xeSub1 = xmlDoc.CreateElement(“title”);
查找Employees节点:XmlNode root = xmlDoc.SelectSingleNode(“Employees”);
添加节点:xe1.AppendChild(xeSub1);
更改节点的属性:xe.SetAttribute(“Name”, “李明明”);
移除xe的ID属性:xe.RemoveAttribute(“ID”);
删除节点title:xe.RemoveChild(xe2);
示例:写入xml
1、创建xml文档
public void CreateXMLDocument(){ XmlDocument xmlDoc = new XmlDocument(); //加入XML的声明段落,<?xml version="1.0" encoding="gb2312"?> XmlDeclaration xmlDeclar; xmlDeclar = xmlDoc.CreateXmlDeclaration("1.0", "gb2312", null); xmlDoc.AppendChild(xmlDeclar); //加入Employees根元素 XmlElement xmlElement = xmlDoc.CreateElement("", "Employees", ""); xmlDoc.AppendChild(xmlElement); //添加节点 XmlNode root = xmlDoc.SelectSingleNode("Employees"); XmlElement xe1 = xmlDoc.CreateElement("Node"); xe1.SetAttribute("Name", "薪薪代码"); xe1.SetAttribute("ISB", "2-3631-4"); //添加子节点 XmlElement xeSub1 = xmlDoc.CreateElement("title"); xeSub1.InnerText = "学习VS"; xe1.AppendChild(xeSub1); XmlElement xeSub2 = xmlDoc.CreateElement("price"); xe1.AppendChild(xeSub2); XmlElement xeSub3 = xmlDoc.CreateElement("weight"); xeSub3.InnerText = "20"; xeSub2.AppendChild(xeSub3); root.AppendChild(xe1); xmlDoc.Save("D:\\book.xml");//保存的路径}
生成的xml文件如下:
<?xml version="1.0" encoding="GB2312"?>-<Employees>- <Node ISB="2-3631-4" Name="薪薪代码"> <title>学习VS</title>- <price> <weight>20</weight> </price> </Node></Employees>
2 、增加节点
XmlDocument xmlDoc = new XmlDocument();xmlDoc.Load("D:\\book.xml");//找到xml文件XmlNode root = xmlDoc.SelectSingleNode("Employees");//查找Employees节点XmlElement xe1 = xmlDoc.CreateElement("Node2");//添加Node2节点xe1.SetAttribute("Name", "张飞");XmlElement xeSub1 = xmlDoc.CreateElement("title");//定义子节点xeSub1.InnerText = "心情好";xe1.AppendChild(xeSub1);//添加节点到Node2root.AppendChild(xe1);//添加节点到EmployeesxmlDoc.Save("D:\\book.xml");
结果:
<?xml version="1.0" encoding="GB2312"?> -<Employees> -<Node ISB="2-3631-4" Name="薪薪代码"> <title>学习VS</title>- <price> <weight>20</weight> </price> </Node>- <Node2 Name="张三"> <title>心情好</title> </Node2>- <Node2 Name="张三"> <title>心情好</title> </Node2></Employees>
3 、修改节点:
public void ModifyNode(){ XmlDocument xmlDocument = new XmlDocument(); xmlDocument.Load("D:\\book.xml"); XmlNodeList nodeList = xmlDocument.SelectSingleNode("Employees").ChildNodes;//获取Employees节点的所有子节点 foreach (XmlNode xn in nodeList)//遍历 { XmlElement xe = (XmlElement)xn; if (xe.GetAttribute("Name") == "薪薪代码") { xe.SetAttribute("Name", "薪薪");//更改节点的属性 XmlNodeList xnl = xe.ChildNodes;//获取xe的所有子节点 foreach (XmlNode xn1 in xnl) { XmlElement xe2 = (XmlElement)xn1;//将节点xn1的属性转换为XmlElement if (xe2.Name == "title")//找到节点名字为title的节点 { xe2.InnerText = "今天天气不好"; } if (xe2.Name == "price") { XmlNodeList xnl2 = xe2.ChildNodes; foreach (XmlNode xn2 in xnl2) { if (xn2.Name == "weight") { xn2.InnerText = "88"; } } } } } } xmlDocument.Save("D:\\book2.xml");}
运行结果:
<?xml version="1.0" encoding="GB2312"?>-<Employees>-<Node ISB="2-3631-4" Name="薪薪"><title>今天天气不好</title>-<price><weight>88</weight></price></Node>-<Node2 Name="张三"><title>心情好</title></Node2></Employees>
4 、删除节点
public void DeleteNode(){ XmlDocument xmlDocument = new XmlDocument(); xmlDocument.Load("D:\\book1.xml"); XmlNodeList xnl = xmlDocument.SelectSingleNode("Employees").ChildNodes; foreach (XmlNode xn in xnl) { if (xn.Name == "Node") { XmlElement xe = (XmlElement)xn;//将xn的属性转换为XmlElement xe.RemoveAttribute("ID");//移除xe的ID属性 XmlNodeList xnl2 = xe.ChildNodes; for (int i = 0; i < xnl2.Count; i++) { XmlElement xe2 = (XmlElement)xnl2.Item(i); if (xe2.Name == "title") { xe.RemoveChild(xe2);//删除节点title } } } } xmlDocument.Save("D:\\book3.xml");}
结果:
<?xml version="1.0" encoding="GB2312"?>-<Employees>-<Node ISB="2-3631-4" Name="薪薪">-<price><weight>20</weight></price></Node>-<Node2 Name="张三"><title>心情好</title></Node2>-<Node2 Name="张三"><title>心情好</title></Node2></Employees>
c#读取xml文件
xml文件如下:
<?xml version="1.0" encoding="utf-8" ?><configurationN> <ServerAddress>1143</ServerAddress> <ID>192.168</ID> </configurationN>
在写入xml文件时,最主要使用了两个方法:Load和Save。
Load:初始化xml文档,以便项目文件获取具体的xml节点的值。
public void Load(string path){ try { XmlDocument xmlDocument = new XmlDocument(); xmlDocument.Load(path); XmlNodeList xnl = xmlDocument.SelectSingleNode(managerNode).ChildNodes; foreach (XmlNode xn in xnl) { if (xn.Name == configuration_ServerAddress) { ServerAddress = xn.InnerText; } } } catch(Exception ex) { }}
Save:在项目系统中进行修改配置文件值后,需要对xml进行重新保存
public void Save(string path){ try { XmlDocument xmlDocument = new XmlDocument(); xmlDocument.Load(path); XmlNodeList xnl = xmlDocument.SelectSingleNode(managerNode).ChildNodes; foreach (XmlNode xn in xnl) { if (xn.Name == configuration_ServerAddress) { xn.InnerText = ServerAddress; } } xmlDocument.Save(path); } catch (Exception ex) { }}
此处将所有代码都贴出来,方便下次实现。因为项目是WPF文件,而且都是简单控件,所以只贴出后台代码。
class ConfigurationManager:INotifyPropertyChanged{ public const string managerNode = "configurationN";//根节点 public const string configuration_ServerAddress = "ServerAddress";//子节点 private string _ServerAddress; public string ServerAddress { get { return _ServerAddress; } set { _ServerAddress = value; NotifyPropertyChanged("ServerAddress"); } } public void Load(string path) { try { XmlDocument xmlDocument = new XmlDocument(); xmlDocument.Load(path); XmlNodeList xnl = xmlDocument.SelectSingleNode(managerNode).ChildNodes; foreach (XmlNode xn in xnl) { if (xn.Name == configuration_ServerAddress) { ServerAddress = xn.InnerText; } } } catch(Exception ex) { } } public void Save(string path) { try { XmlDocument xmlDocument = new XmlDocument(); xmlDocument.Load(path); XmlNodeList xnl = xmlDocument.SelectSingleNode(managerNode).ChildNodes; foreach (XmlNode xn in xnl) { if (xn.Name == configuration_ServerAddress) { xn.InnerText = ServerAddress; } } xmlDocument.Save(path); } catch (Exception ex) { } } public event PropertyChangedEventHandler PropertyChanged; private void NotifyPropertyChanged(string propertyName) { if (PropertyChanged != null) { PropertyChanged(this, new PropertyChangedEventArgs(propertyName)); } } public static ConfigurationManager Instance = new ConfigurationManager();}public partial class MainWindow : Window{ public MainWindow() { InitializeComponent(); Start(); this.tb1.Text = ConfigurationManager.Instance.ServerAddress.ToString(); } private string path = "CONFIG\\System.xml"; private void button1_Click(object sender, RoutedEventArgs e) { ConfigurationManager.Instance.ServerAddress = this.tb1.Text; ConfigurationManager.Instance.Save(path); } private void button2_Click(object sender, RoutedEventArgs e) { Application.Current.Shutdown(); } private void Start() { ConfigurationManager.Instance.Load(path); }}
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