转：XML的几种读取，修改方式？VB.NET
1，读取XML
Imports System.Xml
Imports System.Web.HttpContext
Public Sub getPro()
Dim FilePath As String = Current.Server.MapPath("define_auth.xml")
Dim re As XmlTextReader = New XmlTextReader(FilePath)
Dim name As String
Try
While re.Read
Select Case re.NodeType
Case XmlNodeType.Element
name = re.Name
Case XmlNodeType.Text
setProperty(name, re.Value)
End Select
End While
Catch ex As Exception
Throw ex
End Try
End Sub
'name :XML Node的名字
'Nodetext :XML Node的值
Private Sub setProperty(ByVal NodeName As String, ByVal NodeValue As String)
Select Case NodeName
Case "provider"
sqlProvider = NodeValue
Case "connectionstring"
connectionStr = NodeValue
End Select
End Sub
2,下面是转载别人的部分，重写成了VB.NET
Dim xmldoc As XmlDocument
Dim xmlnode As xmlnode
Dim xmlelem As XmlElement
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
xmldoc = New XmlDocument
'日本语<?xml version="1.0" encoding="shift_jis"?>
Dim xmldecl As XmlDeclaration
xmldecl = xmldoc.CreateXmlDeclaration("1.0", "shift_jis", String.Empty)
xmldoc.AppendChild(xmldecl)
'add a new root element
xmlelem = xmldoc.CreateElement("", "Employees", "")
xmldoc.AppendChild(xmlelem)
'add other elements
Dim i As New Integer
For i = 1 To 3
Dim root As XmlNode = xmldoc.SelectSingleNode("Employees") 'search <Employees>
Dim xe1 As XmlElement = xmldoc.CreateElement("Node") 'create <Node>
xe1.SetAttribute("genre", "Liu")
xe1.SetAttribute("ISBN", "2-3631-4")
Dim xesub1 As XmlElement = xmldoc.CreateElement("title")
xesub1.InnerText = "Book1"
xe1.AppendChild(xesub1) 'add to <node>
Dim xesub2 As XmlElement = xmldoc.CreateElement("author")
xesub2.InnerText = "Hou"
xe1.AppendChild(xesub2)
Dim xesub3 As XmlElement = xmldoc.CreateElement("price")
xesub3.InnerText = "58.3"
xe1.AppendChild(xesub3)
root.AppendChild(xe1) 'add to <Employees>
Next
xmldoc.Save(Server.MapPath("data.xml"))
End Sub
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
Dim xmlWriter As XmlTextWriter
Dim strFilename As String = Server.MapPath("data1.xml")
xmlWriter = New XmlTextWriter(strFilename, System.Text.Encoding.Default)
xmlWriter.Formatting = Formatting.Indented
xmlWriter.WriteStartDocument()
xmlWriter.WriteStartElement("Employees")
xmlWriter.WriteStartElement("Node")
xmlWriter.WriteAttributeString("genre", "Li")
xmlWriter.WriteAttributeString("ISBN", "2-3631-4")
xmlWriter.WriteStartElement("title")
xmlWriter.WriteString("Book2")
xmlWriter.WriteEndElement()
xmlWriter.WriteStartElement("author")
xmlWriter.WriteString("Jia")
xmlWriter.WriteEndElement()
xmlWriter.WriteStartElement("price")
xmlWriter.WriteString("58.3")
xmlWriter.WriteEndElement()
xmlWriter.WriteEndElement()
xmlWriter.Close()
End Sub
Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click
Dim xmlDoc As XmlDocument = New XmlDocument
xmlDoc.Load(Server.MapPath("data.xml"))
Dim root As XmlNode = xmlDoc.SelectSingleNode("Employees")
Dim xe1 As XmlElement = xmlDoc.CreateElement("Node")
xe1.SetAttribute("genre", "張さん")
xe1.SetAttribute("ISBN", "1-1111-1")
Dim xesub1 As XmlElement = xmlDoc.CreateElement("title")
xesub1.InnerText = "New Book"
xe1.AppendChild(xesub1)
Dim xesub2 As XmlElement = xmlDoc.CreateElement("author")
xesub2.InnerText = "H"
xe1.AppendChild(xesub2)
Dim xesub3 As XmlElement = xmlDoc.CreateElement("price")
xesub3.InnerText = "158.3"
xe1.AppendChild(xesub3)
root.AppendChild(xe1)
xmlDoc.Save(Server.MapPath("data.xml"))
End Sub
Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click
Dim xmldoc As New XmlDocument
xmldoc.Load(Server.MapPath("data.xml"))
Dim nodeList As XmlNodeList = xmldoc.SelectSingleNode("Employees").ChildNodes
For Each xn As XmlNode In nodeList
Dim xe As XmlElement
xe = xn
'xe = (XmlElement)xn
If xe.GetAttribute("genre") = "張さん" Then
xe.SetAttribute("genre", "update張さん")
Dim nls As XmlNodeList = xe.ChildNodes
For Each xn1 As XmlNode In nls
Dim xe2 As XmlElement
xe2 = xn1
'xe2 =(XmlElement)xn1
If xe2.Name = "author" Then
xe2.InnerText = "量"
End If
Next
End If
Next
xmldoc.Save(Server.MapPath("data.xml"))
End Sub
Private Sub Button5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button5.Click
Dim xmldoc As XmlDocument = New XmlDocument
xmldoc.Load(Server.MapPath("data.xml"))
Dim nodeList As XmlNodeList = xmldoc.SelectSingleNode("Employees").ChildNodes
For Each xn As XmlNode In nodeList
Dim xe As XmlElement
xe = xn
xe.SetAttribute("test", "111111")
Dim xesub As XmlElement = xmldoc.CreateElement("flag")
xesub.InnerText = "1"
xe.AppendChild(xesub)
Next
xmldoc.Save(Server.MapPath("data.xml"))
End Sub
Private Sub Button6_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button6.Click
Dim xmldoc As XmlDocument = New XmlDocument
xmldoc.Load(Server.MapPath("data.xml"))
Dim xnl As XmlNodeList = xmldoc.SelectSingleNode("Employees").ChildNodes
For Each xn As XmlNode In xnl
Dim xe As XmlElement
xe = xn
xe.RemoveAttribute("genre")
Dim nls As XmlNodeList = xe.ChildNodes
For Each xn1 As XmlNode In nls
Dim xe2 As XmlElement
xe2 = xn1
If xe2.Name = "flag" Then
xe.RemoveChild(xe2)
End If
Next
Next
xmldoc.Save(Server.MapPath("data.xml"))
End Sub
Private Sub Button7_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button7.Click
Dim xmlDoc As XmlDocument = New XmlDocument
xmlDoc.Load(Server.MapPath("data.xml"))
Dim root As XmlNode = xmlDoc.SelectSingleNode("Employees")
Dim xnl As XmlNodeList = xmlDoc.SelectSingleNode("Employees").ChildNodes
Dim i As Integer
For i = 0 To i < xnl.Count
Dim xe As XmlElement
xe = xnl.Item( i )
If xe.GetAttribute("genre") = "張さん" Then
root.RemoveChild(xe)
If i < xnl.Count Then i = i - 1
End If
Next
xmlDoc.Save(Server.MapPath("data.xml"))
End Sub
Private Sub Button8_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button8.Click
Dim myFile As System.IO.StreamReader = _
New System.IO.StreamReader(Server.MapPath("data.xml"), System.Text.Encoding.Default)
'Attention System.Text.Encoding.Default
Dim myString As String = myFile.ReadToEnd() 'myString was read
myFile.Close()
End Sub
摘自http://www.cnblogs.com/Ronin/archive/2005/09/13/236006.html