C# XML文件创建、追加、读取与修改

1 创建XML

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Xml;

namespace 创建XML
{
    class Program
    {
        static void Main(string[] args)
        {
            XmlDocument doc = new XmlDocument();                                       //创建XML文档对象
            XmlDeclaration dec = doc.CreateXmlDeclaration("1.0", "utf-8", null);       //创建第一行描述信息，并添加到doc文档中
            doc.AppendChild(dec);
            XmlElement books = doc.CreateElement("Books");                             //创建根节点，并添加到doc文档中
            doc.AppendChild(books);

            XmlElement book1 = doc.CreateElement("Book");                              //创建一级子节点Book，将Book添加到根节点
            books.AppendChild(book1);
            book1.SetAttribute("Index", "1");
            book1.SetAttribute("Title", "红楼梦");
            //给book1添加子节点
            XmlElement price1 = doc.CreateElement("Price");
            price1.InnerText = "10元";
            book1.AppendChild(price1);
            XmlElement des1 = doc.CreateElement("Des");
            des1.InnerText = "好看";
            book1.AppendChild(des1);
            XmlElement pages1 = doc.CreateElement("Pages");
            pages1.InnerText = "800页";
            book1.AppendChild(pages1);

            XmlElement book2 = doc.CreateElement("Book");                               //创建一级子节点Book，将Book添加到根节点
            books.AppendChild(book2);
            book2.SetAttribute("Index", "2");
            book2.SetAttribute("Title", "三国演义");
            //给book2添加子节点
            XmlElement price2 = doc.CreateElement("Price");
            price2.InnerText = "20元";
            book2.AppendChild(price2);
            XmlElement des2 = doc.CreateElement("Des");
            des2.InnerText = "还可以";
            book2.AppendChild(des2);
            XmlElement pages2 = doc.CreateElement("Pages");
            pages2.InnerText = "600页";
            book2.AppendChild(pages2);

            doc.Save("Books.xml");
            Console.WriteLine("保存成功");
            Console.ReadKey();
        }
    }
}

2 追加XML

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Xml;

namespace 追加XML
{
    class Program
    {
        static void Main(string[] args)
        {
            XmlDocument doc = new XmlDocument();
            XmlElement books;
            if (File.Exists("Books.xml"))
            {
                doc.Load("Books.xml");                                                        //如果文件存在 加载XML
                books = doc.DocumentElement;                                                  //获得文件的根节点
            }
            else
            {
                //如果文件不存在，重新创建
                XmlDeclaration dec = doc.CreateXmlDeclaration("1.0", "utf-8", null);
                doc.AppendChild(dec);
                books = doc.CreateElement("Books");
                doc.AppendChild(books);
            }
            XmlElement book1 = doc.CreateElement("Book");                                    //创建一级子节点Book，将Book添加到根节点
            books.AppendChild(book1);
            book1.SetAttribute("Index", "n");
            book1.SetAttribute("Title", "西游记");
            //给book1添加子节点
            XmlElement price1 = doc.CreateElement("Price");
            price1.InnerText = "30元";
            book1.AppendChild(price1);
            XmlElement des1 = doc.CreateElement("Des");
            des1.InnerText = "非常好看";
            book1.AppendChild(des1);
            XmlElement pages1 = doc.CreateElement("Pages");
            pages1.InnerText = "550页";
            book1.AppendChild(pages1);

            doc.Save("Books.xml");
            Console.WriteLine("保存成功");
            Console.ReadKey();
        }
    }
}

3 读取与修改XML

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Xml;

namespace 读取与修改
{
    class Program
    {
        static void Main(string[] args)
        {
            XmlDocument doc = new XmlDocument();
            doc.Load("Books.xml");                                                                 //加载要读取的XML
            XmlElement books = doc.DocumentElement;                                                //获得根节点

            //读取标签内容
            XmlNodeList xnl1 = books.ChildNodes;                                                   //获得子节点 返回节点的集合
            foreach (XmlNode item in xnl1)
            {
                Console.WriteLine(item.InnerText);                                                 //获取或设置节点及其所有子节点的串联值。
            }

            //读取标签属性
            XmlNodeList xnl2 = doc.SelectNodes("/Books/Book");
            foreach (XmlNode node in xnl2)
            {
                Console.Write(node.Attributes["Title"].Value);
                Console.WriteLine(node.Attributes["Index"].Value);
            }

            //修改标签内容的值
            XmlNode xn = doc.SelectSingleNode("/Books/Book/Price");
            xn.InnerText = "99.99元";
            doc.Save("NewBooks.xml");
            Console.WriteLine("保存成功");

            //修改标签属性的值1
            //XmlNode xn = doc.SelectSingleNode("/Books/Book[@Title='西游记']");         	//"Books.xml"中有两个'西游记'，只匹配第一个
            //xn.Attributes["Title"].Value = "西游记1";
            //xn.Attributes["Index"].Value = "3";
            //doc.Save("NewBooks.xml");
            //Console.WriteLine("保存成功");

            //修改标签属性的值2
            //XmlNodeList xn = doc.SelectNodes("/Books/Book[@Title='西游记']");            	//"Books.xml"中有两个'西游记'，只匹配第一个
            //foreach (XmlNode node in xnl2)
            //{
            //    node.Attributes["Title"].Value = "西游记1";
            //    node.Attributes["Index"].Value = "3";
            //}
            //doc.Save("NewBooks.xml");
            //Console.WriteLine("保存成功");

            //修改标签属性的值3
            //XmlNodeList xn = doc.SelectNodes("/Books/Book");                              //全部修改
            //foreach (XmlNode node in xn)
            //{
            //    node.Attributes["Title"].Value = "西游记1";
            //    node.Attributes["Index"].Value = "3";
            //}
            //doc.Save("NewBooks.xml");
            //Console.WriteLine("保存成功");

            Console.ReadKey();
        }
    }
}