Question

搜索互联网找到了不少于700种不同的方式和意见来完成我想要做的事情，我只想知道最简单，最防弹的方式。

考虑以下XML文件：

<?xml version="1.0" encoding="utf-8" ?>
<xmlCommands>
<command>
<core>
<host>foo</host>
</core>
<protectedServers>
<hostName>bar</hostName>
</protectedServers>
<name>DeleteAgent</name>
</command>
</xmlCommands>

我只想提取字符串“bar”，它位于<hostName></hostName>内我可以使用简单的字符串函数轻松地完成此操作，但我想使用其中一个.NET XML类/方法。

Answer 1

您可以使用Linq to XML：

dim xDoc as xdocument = xdocument.parse(myXmlFile)
dim bar = (from y in xDoc.descendant("hostName") _
           select y.Value _
          ).take(1).singleordefault

或传统的XML类：

dim xDoc as new xml.xmldocument()
xDoc.Load(myXmlFile)
dim node as xml.xmlnode = xdoc.selectSingleNode(xPathStringtoNode)
dim bar as string = node.value

Answer 2

以下是使用XPATH的示例：

Private Sub Button7_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button7.Click
  'N.B. Need to Import System.Xml
  Dim xdc As New XmlDocument
  xdc.Load("C:\Junk\Junk.XML")
  '1. Search for a node at a particular place
  Dim strXpath1 As String = "/xmlCommands/command/protectedServers/hostName" 'N.B. case sensitive
  Dim xnd1 As XmlNode = xdc.SelectSingleNode(strXpath1)
  If xnd1 IsNot Nothing Then
    MsgBox(xnd1.FirstChild.Value)
  Else
    MsgBox(strXpath1 & " not found")
  End If
  '2. Search for first match in document
  Dim strXpath2 As String = "//hostName" 'N.B. case sensitive
  Dim xnd2 As XmlNode = xdc.SelectSingleNode(strXpath2)
  If xnd2 IsNot Nothing Then
    MsgBox(xnd2.FirstChild.Value)
  Else
    MsgBox(strXpath2 & " not found")
  End If
End Sub

VB XML类与字符串类

2 个答案: