vb.net 教程 4-10 XML文件操作 1

XML(EXtensible Markup Language）：可扩展标记语言目前被广泛的运用，本大节讨论如何操作xml文件。

关于Xml语法结构，请自行查找相关资料。

本大节使用到的Xml文件为 books.xml：

<?xml version="1.0" encoding="UTF-8"?>
<BookStore>
  <Book ISBN="9787302424260">
    <TITLE>星球大战：幽灵的威胁</TITLE>
    <AUTHOR>特里·布鲁克斯</AUTHOR>
    <COUNTRY>美国</COUNTRY>
    <PRICE>48.00</PRICE>
    <YEAR>1985</YEAR>
  </Book>
  <Book ISBN="9787302425274">
    <TITLE>星球大战：克隆人的进攻</TITLE>
    <AUTHOR>R. A. 萨尔瓦多</AUTHOR>
    <COUNTRY>美国</COUNTRY>
    <PRICE>48.00</PRICE>
    <YEAR>1985</YEAR>
  </Book>
  <Book ISBN="9787302426899">
    <TITLE>星球大战：西斯的复仇</TITLE>
    <AUTHOR>马修·斯托弗</AUTHOR>
    <COUNTRY>美国</COUNTRY>
    <PRICE>58.00</PRICE>
    <YEAR>1985</YEAR>
  </Book>
  <Book ISBN="9787302421146">
    <TITLE>星球大战：新的希望</TITLE>
    <AUTHOR>乔治·卢卡斯</AUTHOR>
    <COUNTRY>美国</COUNTRY>
    <PRICE>35.00</PRICE>
    <YEAR>1985</YEAR>
  </Book>
  <Book ISBN="9787302421122">
    <TITLE>星球大战：帝国反击战</TITLE>
    <AUTHOR>唐纳德·F.格卢特</AUTHOR>
    <COUNTRY>美国</COUNTRY>
    <PRICE>35.00</PRICE>
    <YEAR>1985</YEAR>
  </Book>
  <Book ISBN="9787302421108">
    <TITLE>星球大战：绝地归来</TITLE>
    <AUTHOR>詹姆斯·卡恩</AUTHOR>
    <COUNTRY>美国</COUNTRY>
    <PRICE>35.00</PRICE>
    <YEAR>1985</YEAR>
  </Book>
  <Book ISBN="9787562849896">
    <TITLE>星球大战：原力觉醒</TITLE>
    <AUTHOR>迪士尼公司</AUTHOR>
    <COUNTRY>美国</COUNTRY>
    <PRICE>48.00</PRICE>
    <YEAR>2016</YEAR>
  </Book>
</BookStore>

主窗体设计界面：

先看看如何载入并显示xml中的数据：

添加对XML命名空间的引用：

Imports System.Xml

Dim xmlDoc As XmlDocument

Private Sub Button1_Click(sender As Object,e As EventArgs) Handles Button1.Click
        xmlDoc = New XmlDocument()
        xmlDoc.Load("d:books.xml")
        Call showXML()
    End Sub

Imports System.IO

Private Sub Button1_Click(sender As Object,e As EventArgs) Handles Button1.Click
        xmlDoc = New XmlDocument()
        Dim myreader As TextReader = New StreamReader("d:books.xml")
        Dim mystring As String = myreader.ReadToEnd
        xmlDoc.LoadXml(mystring)
        myreader.Close()
        Call showXML()
    End Sub

Private Sub showXML()
        ListView1.Items.Clear()

        Dim rootElement As XmlElement
        rootElement = xmlDoc.DocumentElement

        Dim xmlNl As XmlNodeList = rootElement.ChildNodes
        Dim lvItem As ListViewItem
        For Each xmlchild As XmlNode In xmlNl
            lvItem = New ListViewItem(xmlchild.Attributes("ISBN").Value)

            For Each xmlgrandchild As XmlNode In xmlchild.ChildNodes
                lvItem.SubItems.Add(xmlgrandchild.InnerText)
            Next
            ListView1.Items.Add(lvItem)
        Next
    End Sub