Xml 基于节点属性值覆盖元素值_Xml_Vb.net_Visual Studio 2010_Linq To Xml

Xml 基于节点属性值覆盖元素值

xml vb.net visual-studio-2010

Xml 基于节点属性值覆盖元素值,xml,vb.net,visual-studio-2010,linq-to-xml,Xml,Vb.net,Visual Studio 2010,Linq To Xml,我的xml文档的结构如下： <Root> <Word ID="23"> <Type>auxiliary</Type> <English></English> <Thai></Thai> <Meaning></Meaning> <Audio>Dictionary Resources\Sound Files\23.wma<

我的xml文档的结构如下：

<Root>
  <Word ID="23">
    <Type>auxiliary</Type>
    <English></English>
    <Thai></Thai>
    <Meaning></Meaning>
    <Audio>Dictionary Resources\Sound Files\23.wma</Audio>
    <Picture>Dictionary Resources\Picture Files\23.jpg</Picture>
    <Transliteration></Transliteration>
    <Timestamp />
  </Word>
...
</Root>

有多种方法可以做到这一点。您可以将

和

语法与

XDocument

对象一起使用，向下钻取到所需的元素，如下所示：

    Sub Timestamp(ByVal IDChosen As String)
    Dim Dictionary As XDocument = XDocument.Load("Dictionary Resources\Dictionary.xml")
    Dictionary.Root.Elements("Word").Atrribute"ID"(IDChosen).Value = DateTime.Now
    Dictionary.Save("Dictionary Resources\Dictionary.xml")
    End Sub

Sub Timestamp(idChosen As String)
    Dim doc As XDocument = XDocument.Load("Dictionary Resources\Dictionary.xml")
    Dim word As XElement = doc.<Root>.<Word>.FirstOrDefault(Function(x) x.@ID = idChosen)
    If word IsNot Nothing Then
        word.<Timestamp>.First().SetValue(Date.Now)
        doc.Save("Dictionary Resources\Dictionary.xml")
    End If
End Sub

Sub Timestamp(idChosen As String)
    Dim doc As XDocument = XDocument.Load("Dictionary Resources\Dictionary.xml")
    Dim timeStamp As XElement = doc.XPathSelectElement("/Root/Word[@ID='" & idChosen & "']/Timestamp")
    If timeStamp IsNot Nothing Then
        timeStamp.SetValue(Date.Now)
        doc.Save("Dictionary Resources\Dictionary.xml")
    End If
End Sub

Sub Timestamp(idChosen As String)
    Dim doc As XDocument = XDocument.Load("Dictionary Resources\Dictionary.xml")
    Dim t As XElement = _
        (
        From word In doc.<Root>.<Word> 
        Where word.@ID = idChosen 
        Select word.<Timestamp>.FirstOrDefault()
        ).FirstOrDefault()
    If t IsNot Nothing Then
        t.SetValue(Date.Now)
        doc.Save("Dictionary Resources\Dictionary.xml")
    End If
End Sub

Sub Timestamp(idChosen As String)
    Dim doc As XDocument = XDocument.Load("Dictionary Resources\Dictionary.xml")
    Dim t As XElement = _
        (
        From word In doc.Root.Elements("Word") 
        Where word.Attributes("ID").Any(Function(x) x.Value = idChosen) 
        Select word.Element("Timestamp")
        ).FirstOrDefault()
    If t IsNot Nothing Then
        t.SetValue(Date.Now)
        doc.Save("Dictionary Resources\Dictionary.xml")
    End If
End Sub

Dim word As XElement = doc...<Word>.FirstOrDefault(Function(x) x.@ID = idChosen)

或者，可以使用查询语法选择元素，如下所示：

    Sub Timestamp(ByVal IDChosen As String)
    Dim Dictionary As XDocument = XDocument.Load("Dictionary Resources\Dictionary.xml")
    Dictionary.Root.Elements("Word").Atrribute"ID"(IDChosen).Value = DateTime.Now
    Dictionary.Save("Dictionary Resources\Dictionary.xml")
    End Sub

Sub Timestamp(idChosen As String)
    Dim doc As XDocument = XDocument.Load("Dictionary Resources\Dictionary.xml")
    Dim word As XElement = doc.<Root>.<Word>.FirstOrDefault(Function(x) x.@ID = idChosen)
    If word IsNot Nothing Then
        word.<Timestamp>.First().SetValue(Date.Now)
        doc.Save("Dictionary Resources\Dictionary.xml")
    End If
End Sub

Sub Timestamp(idChosen As String)
    Dim doc As XDocument = XDocument.Load("Dictionary Resources\Dictionary.xml")
    Dim timeStamp As XElement = doc.XPathSelectElement("/Root/Word[@ID='" & idChosen & "']/Timestamp")
    If timeStamp IsNot Nothing Then
        timeStamp.SetValue(Date.Now)
        doc.Save("Dictionary Resources\Dictionary.xml")
    End If
End Sub

Sub Timestamp(idChosen As String)
    Dim doc As XDocument = XDocument.Load("Dictionary Resources\Dictionary.xml")
    Dim t As XElement = _
        (
        From word In doc.<Root>.<Word> 
        Where word.@ID = idChosen 
        Select word.<Timestamp>.FirstOrDefault()
        ).FirstOrDefault()
    If t IsNot Nothing Then
        t.SetValue(Date.Now)
        doc.Save("Dictionary Resources\Dictionary.xml")
    End If
End Sub

Sub Timestamp(idChosen As String)
    Dim doc As XDocument = XDocument.Load("Dictionary Resources\Dictionary.xml")
    Dim t As XElement = _
        (
        From word In doc.Root.Elements("Word") 
        Where word.Attributes("ID").Any(Function(x) x.Value = idChosen) 
        Select word.Element("Timestamp")
        ).FirstOrDefault()
    If t IsNot Nothing Then
        t.SetValue(Date.Now)
        doc.Save("Dictionary Resources\Dictionary.xml")
    End If
End Sub

Dim word As XElement = doc...<Word>.FirstOrDefault(Function(x) x.@ID = idChosen)

或者，如果您不关心实际的XML文档结构，只想找到具有该ID的第一个

Word

元素，而不管它位于文档树中的何处，您可以这样选择元素：

    Sub Timestamp(ByVal IDChosen As String)
    Dim Dictionary As XDocument = XDocument.Load("Dictionary Resources\Dictionary.xml")
    Dictionary.Root.Elements("Word").Atrribute"ID"(IDChosen).Value = DateTime.Now
    Dictionary.Save("Dictionary Resources\Dictionary.xml")
    End Sub

Sub Timestamp(idChosen As String)
    Dim doc As XDocument = XDocument.Load("Dictionary Resources\Dictionary.xml")
    Dim word As XElement = doc.<Root>.<Word>.FirstOrDefault(Function(x) x.@ID = idChosen)
    If word IsNot Nothing Then
        word.<Timestamp>.First().SetValue(Date.Now)
        doc.Save("Dictionary Resources\Dictionary.xml")
    End If
End Sub

Sub Timestamp(idChosen As String)
    Dim doc As XDocument = XDocument.Load("Dictionary Resources\Dictionary.xml")
    Dim timeStamp As XElement = doc.XPathSelectElement("/Root/Word[@ID='" & idChosen & "']/Timestamp")
    If timeStamp IsNot Nothing Then
        timeStamp.SetValue(Date.Now)
        doc.Save("Dictionary Resources\Dictionary.xml")
    End If
End Sub

Sub Timestamp(idChosen As String)
    Dim doc As XDocument = XDocument.Load("Dictionary Resources\Dictionary.xml")
    Dim t As XElement = _
        (
        From word In doc.<Root>.<Word> 
        Where word.@ID = idChosen 
        Select word.<Timestamp>.FirstOrDefault()
        ).FirstOrDefault()
    If t IsNot Nothing Then
        t.SetValue(Date.Now)
        doc.Save("Dictionary Resources\Dictionary.xml")
    End If
End Sub

Sub Timestamp(idChosen As String)
    Dim doc As XDocument = XDocument.Load("Dictionary Resources\Dictionary.xml")
    Dim t As XElement = _
        (
        From word In doc.Root.Elements("Word") 
        Where word.Attributes("ID").Any(Function(x) x.Value = idChosen) 
        Select word.Element("Timestamp")
        ).FirstOrDefault()
    If t IsNot Nothing Then
        t.SetValue(Date.Now)
        doc.Save("Dictionary Resources\Dictionary.xml")
    End If
End Sub

Dim word As XElement = doc...<Word>.FirstOrDefault(Function(x) x.@ID = idChosen)

或：

就我个人而言，我建议使用XPath方法来选择节点，因为它简短、简单、易于阅读，而且它使用的是行业标准的查询语言，而不是Microsoft专有的LINQ技术，但这只是我的想法：）

有多种方法可以做到这一点。您可以将

和

语法与

XDocument

对象一起使用，向下钻取到所需的元素，如下所示：

    Sub Timestamp(ByVal IDChosen As String)
    Dim Dictionary As XDocument = XDocument.Load("Dictionary Resources\Dictionary.xml")
    Dictionary.Root.Elements("Word").Atrribute"ID"(IDChosen).Value = DateTime.Now
    Dictionary.Save("Dictionary Resources\Dictionary.xml")
    End Sub

Sub Timestamp(idChosen As String)
    Dim doc As XDocument = XDocument.Load("Dictionary Resources\Dictionary.xml")
    Dim word As XElement = doc.<Root>.<Word>.FirstOrDefault(Function(x) x.@ID = idChosen)
    If word IsNot Nothing Then
        word.<Timestamp>.First().SetValue(Date.Now)
        doc.Save("Dictionary Resources\Dictionary.xml")
    End If
End Sub

Sub Timestamp(idChosen As String)
    Dim doc As XDocument = XDocument.Load("Dictionary Resources\Dictionary.xml")
    Dim timeStamp As XElement = doc.XPathSelectElement("/Root/Word[@ID='" & idChosen & "']/Timestamp")
    If timeStamp IsNot Nothing Then
        timeStamp.SetValue(Date.Now)
        doc.Save("Dictionary Resources\Dictionary.xml")
    End If
End Sub

Sub Timestamp(idChosen As String)
    Dim doc As XDocument = XDocument.Load("Dictionary Resources\Dictionary.xml")
    Dim t As XElement = _
        (
        From word In doc.<Root>.<Word> 
        Where word.@ID = idChosen 
        Select word.<Timestamp>.FirstOrDefault()
        ).FirstOrDefault()
    If t IsNot Nothing Then
        t.SetValue(Date.Now)
        doc.Save("Dictionary Resources\Dictionary.xml")
    End If
End Sub

Sub Timestamp(idChosen As String)
    Dim doc As XDocument = XDocument.Load("Dictionary Resources\Dictionary.xml")
    Dim t As XElement = _
        (
        From word In doc.Root.Elements("Word") 
        Where word.Attributes("ID").Any(Function(x) x.Value = idChosen) 
        Select word.Element("Timestamp")
        ).FirstOrDefault()
    If t IsNot Nothing Then
        t.SetValue(Date.Now)
        doc.Save("Dictionary Resources\Dictionary.xml")
    End If
End Sub

Dim word As XElement = doc...<Word>.FirstOrDefault(Function(x) x.@ID = idChosen)

或者，可以使用查询语法选择元素，如下所示：

    Sub Timestamp(ByVal IDChosen As String)
    Dim Dictionary As XDocument = XDocument.Load("Dictionary Resources\Dictionary.xml")
    Dictionary.Root.Elements("Word").Atrribute"ID"(IDChosen).Value = DateTime.Now
    Dictionary.Save("Dictionary Resources\Dictionary.xml")
    End Sub

Sub Timestamp(idChosen As String)
    Dim doc As XDocument = XDocument.Load("Dictionary Resources\Dictionary.xml")
    Dim word As XElement = doc.<Root>.<Word>.FirstOrDefault(Function(x) x.@ID = idChosen)
    If word IsNot Nothing Then
        word.<Timestamp>.First().SetValue(Date.Now)
        doc.Save("Dictionary Resources\Dictionary.xml")
    End If
End Sub

Sub Timestamp(idChosen As String)
    Dim doc As XDocument = XDocument.Load("Dictionary Resources\Dictionary.xml")
    Dim timeStamp As XElement = doc.XPathSelectElement("/Root/Word[@ID='" & idChosen & "']/Timestamp")
    If timeStamp IsNot Nothing Then
        timeStamp.SetValue(Date.Now)
        doc.Save("Dictionary Resources\Dictionary.xml")
    End If
End Sub

Sub Timestamp(idChosen As String)
    Dim doc As XDocument = XDocument.Load("Dictionary Resources\Dictionary.xml")
    Dim t As XElement = _
        (
        From word In doc.<Root>.<Word> 
        Where word.@ID = idChosen 
        Select word.<Timestamp>.FirstOrDefault()
        ).FirstOrDefault()
    If t IsNot Nothing Then
        t.SetValue(Date.Now)
        doc.Save("Dictionary Resources\Dictionary.xml")
    End If
End Sub

Sub Timestamp(idChosen As String)
    Dim doc As XDocument = XDocument.Load("Dictionary Resources\Dictionary.xml")
    Dim t As XElement = _
        (
        From word In doc.Root.Elements("Word") 
        Where word.Attributes("ID").Any(Function(x) x.Value = idChosen) 
        Select word.Element("Timestamp")
        ).FirstOrDefault()
    If t IsNot Nothing Then
        t.SetValue(Date.Now)
        doc.Save("Dictionary Resources\Dictionary.xml")
    End If
End Sub

Dim word As XElement = doc...<Word>.FirstOrDefault(Function(x) x.@ID = idChosen)

或者，如果您不关心实际的XML文档结构，只想找到具有该ID的第一个

Word

元素，而不管它位于文档树中的何处，您可以这样选择元素：

    Sub Timestamp(ByVal IDChosen As String)
    Dim Dictionary As XDocument = XDocument.Load("Dictionary Resources\Dictionary.xml")
    Dictionary.Root.Elements("Word").Atrribute"ID"(IDChosen).Value = DateTime.Now
    Dictionary.Save("Dictionary Resources\Dictionary.xml")
    End Sub

Sub Timestamp(idChosen As String)
    Dim doc As XDocument = XDocument.Load("Dictionary Resources\Dictionary.xml")
    Dim word As XElement = doc.<Root>.<Word>.FirstOrDefault(Function(x) x.@ID = idChosen)
    If word IsNot Nothing Then
        word.<Timestamp>.First().SetValue(Date.Now)
        doc.Save("Dictionary Resources\Dictionary.xml")
    End If
End Sub

Sub Timestamp(idChosen As String)
    Dim doc As XDocument = XDocument.Load("Dictionary Resources\Dictionary.xml")
    Dim timeStamp As XElement = doc.XPathSelectElement("/Root/Word[@ID='" & idChosen & "']/Timestamp")
    If timeStamp IsNot Nothing Then
        timeStamp.SetValue(Date.Now)
        doc.Save("Dictionary Resources\Dictionary.xml")
    End If
End Sub

Sub Timestamp(idChosen As String)
    Dim doc As XDocument = XDocument.Load("Dictionary Resources\Dictionary.xml")
    Dim t As XElement = _
        (
        From word In doc.<Root>.<Word> 
        Where word.@ID = idChosen 
        Select word.<Timestamp>.FirstOrDefault()
        ).FirstOrDefault()
    If t IsNot Nothing Then
        t.SetValue(Date.Now)
        doc.Save("Dictionary Resources\Dictionary.xml")
    End If
End Sub

Sub Timestamp(idChosen As String)
    Dim doc As XDocument = XDocument.Load("Dictionary Resources\Dictionary.xml")
    Dim t As XElement = _
        (
        From word In doc.Root.Elements("Word") 
        Where word.Attributes("ID").Any(Function(x) x.Value = idChosen) 
        Select word.Element("Timestamp")
        ).FirstOrDefault()
    If t IsNot Nothing Then
        t.SetValue(Date.Now)
        doc.Save("Dictionary Resources\Dictionary.xml")
    End If
End Sub

Dim word As XElement = doc...<Word>.FirstOrDefault(Function(x) x.@ID = idChosen)

或：

就个人而言，我建议使用XPath方法来选择节点，因为它简短、简单、易于阅读，而且它使用的是行业标准的查询语言，而不是Microsoft专有的LINQ技术，但这只是我的想法：）

根据示例XML中的格式，不清楚，如果您正在查找

/Root/Word/Word

，或

/Root/Word

。抱歉，刚刚在post中编辑了xml，它应该是/Root/Word。您正在尝试设置哪个元素的值？是要设置为当前时间的

/Root/Word/Timestamp

元素吗？根据您的psuedo代码，这并不完全清楚。是的，这是我试图将当前时间设置为的/Root/Word/Timestamp。根据示例XML中的格式，如果您正在查找

/Root/Word/Word

，或

/Root/Word

，则不清楚。抱歉，刚刚在post中编辑了XML，它应该是/Root/Word。您要设置哪个元素的值？是要设置为当前时间的

/Root/Word/Timestamp

元素吗？根据您的psuedo代码，这还不完全清楚。是的，我正试图将当前时间设置为/Root/Word/Timestamp。我对@or函数都不熟悉。我所写的其余代码都是使用诸如Dictionary.Root.Elements（“Word”）等引用编写的。是否可以使用以下内容来实现它

Dim t As XElement=（来自Dictionary.Root.Elements（“Word”）中的x，其中x.Attribute（“ID”）=idselected选择x.Elements（“Timestamp”）

感谢您的回答Steven，示例非常好。我同意您的XPath建议，我发现它更容易理解。我对@or函数都不熟悉。我所写的其余代码都是使用诸如Dictionary.Root.Elements（“Word”）等引用编写的。是否可以使用以下内容来实现它

Dim t As XElement=（来自Dictionary.Root.Elements（“Word”）中的x，其中x.Attribute（“ID”）=idselected选择x.Elements（“Timestamp”）

感谢您的回答Steven，示例非常好。我同意您的XPath建议，我发现它更容易理解。