用XmlDocument创建XML文档

public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void btnLoad_Click(object sender, EventArgs e)
{
XmlDocument xmlDoc = new XmlDocument();
xmlDoc.Load("Books.xml");
MessageBox.Show(xmlDoc.InnerXml);
}
//创建文档
private void btnCreate_Click(object sender, EventArgs e)
{
XmlDocument xmlDoc = new XmlDocument();
//建立Xml的定义声明
XmlDeclaration dec = xmlDoc.CreateXmlDeclaration("1.0", "GB2312", null);
xmlDoc.AppendChild(dec);
//创建根节点
XmlElement root = xmlDoc.CreateElement("Books");
xmlDoc.AppendChild(root);
XmlNode book = xmlDoc.CreateElement("Book");
XmlElement title = xmlDoc.CreateElement("Title");
title.InnerText = "SQL Server";
book.AppendChild(title);
XmlElement isbn = xmlDoc.CreateElement("ISBN");
isbn.InnerText = "444444";
book.AppendChild(isbn);
XmlElement author = xmlDoc.CreateElement("Author");
author.InnerText = "jia";
book.AppendChild(author);
XmlElement price = xmlDoc.CreateElement("Price");
price.InnerText = "120";
price.SetAttribute("Unit", "___FCKpd___0quot;);
book.AppendChild(price);
root.AppendChild(book);
xmlDoc.Save("Books.xml");
}

private void btnInsert_Click(object sender, EventArgs e)
{
XmlDocument xmlDoc = new XmlDocument();
xmlDoc.Load("Books.xml");
XmlNode root = xmlDoc.SelectSingleNode("Books");
XmlElement book = xmlDoc.CreateElement("Book");
XmlElement title = xmlDoc.CreateElement("Title");
title.InnerText = "XML";
book.AppendChild(title);
XmlElement isbn = xmlDoc.CreateElement("ISBN");
isbn.InnerText = "333333";
book.AppendChild(isbn);
XmlElement author = xmlDoc.CreateElement("Author");
author.InnerText = "snow";
book.AppendChild(author);
XmlElement price = xmlDoc.CreateElement("Price");
price.InnerText = "120";
price.SetAttribute("Unit", "___FCKpd___0quot;);
book.AppendChild(price);
root.AppendChild(book);
xmlDoc.Save("Books.xml");
MessageBox.Show("数据已写入！");
}

private void btnUpdate_Click(object sender, EventArgs e)
{
XmlDocument xmlDoc = new XmlDocument();
xmlDoc.Load("Books.xml");
//"//Book[@Unit=\"$\"]"
//获取Books节点的所有子节点
XmlNodeList nodeList = xmlDoc.SelectSingleNode("Books//Book").ChildNodes;
//遍历所有子节点
foreach (XmlNode xn in nodeList)
{
//将子节点类型转换为XmlElement类型
XmlElement xe = (XmlElement)xn;
if (xe.Name == "Author")
{
xe.InnerText = "amandag";
}
if (xe.GetAttribute("Unit") == "___FCKpd___0quot;)
{
xe.SetAttribute("Unit", "￥");
}
}
xmlDoc.Save("Books.xml");
}

private void btnDelete_Click(object sender, EventArgs e)
{
XmlDocument xmlDoc = new XmlDocument();
xmlDoc.Load("Books.xml");
XmlNodeList nodeList = xmlDoc.SelectSingleNode("Books//Book").ChildNodes;
//遍历所有子节点
foreach (XmlNode xn in nodeList)
{
//将子节点类型转换为XmlElement类型
XmlElement xe = (XmlElement)xn;
if (xe.Name == "Author")
{
xe.RemoveAll();
}
if (xe.GetAttribute("Unit") == "￥")
{
xe.RemoveAttribute("Unit");
}
}
xmlDoc.Save("Books.xml");
}
}
}