Extensions.DescendantNodes(IEnumerable<T>) Extensions.DescendantNodes(IEnumerable<T>) Extensions.DescendantNodes(IEnumerable<T>) Extensions.DescendantNodes(IEnumerable<T>) Method

定義

ソース コレクション内のすべてのドキュメントおよび要素の子孫ノードのコレクションを返します。Returns a collection of the descendant nodes of every document and element in the source collection.

public:
generic <typename T>
 where T : System::Xml::Linq::XContainer[System::Runtime::CompilerServices::Extension]
 static System::Collections::Generic::IEnumerable<System::Xml::Linq::XNode ^> ^ DescendantNodes(System::Collections::Generic::IEnumerable<T> ^ source);
public static System.Collections.Generic.IEnumerable<System.Xml.Linq.XNode> DescendantNodes<T> (this System.Collections.Generic.IEnumerable<T> source) where T : System.Xml.Linq.XContainer;
static member DescendantNodes : seq<'T (requires 'T :> System.Xml.Linq.XContainer)> -> seq<System.Xml.Linq.XNode> (requires 'T :> System.Xml.Linq.XContainer)
<Extension()>
Public Function DescendantNodes(Of T As XContainer) (source As IEnumerable(Of T)) As IEnumerable(Of XNode)

型パラメーター

T

XContainer に制限された、source 内のオブジェクトの型。The type of the objects in source, constrained to XContainer.

パラメーター

source
IEnumerable<T> IEnumerable<T> IEnumerable<T> IEnumerable<T>

ソース コレクションが格納されている IEnumerable<T>XContainerAn IEnumerable<T> of XContainer that contains the source collection.

戻り値

ソース コレクション内のすべてのドキュメントおよび要素の子孫ノードの、IEnumerable<T>XNodeAn IEnumerable<T> of XNode of the descendant nodes of every document and element in the source collection.

次の例では、2 つの要素のコレクションを取得し、ソース コレクション内のすべての要素のすべての子孫ノードのコレクションを取得します。The following example retrieves a collection of two elements, and then retrieves a collection of all descendant nodes for every element in the source collection. 注意の属性、GrandChild要素はノードとして表示されません。Note that the attribute of the GrandChild element is not surfaced as a node.

XElement xmlTree = XElement.Parse(  
@"<Root>  
    <Child>aaa<GrandChild anAttribute='xyz'>Text</GrandChild>  
        <!--a comment-->  
        <?xml-stylesheet type='text/xsl' href='test.xsl'?>  
    </Child>  
    <Child>ccc<GrandChild>Text</GrandChild>ddd</Child>  
</Root>");  
IEnumerable<XNode> nodes =  
    from node in xmlTree.Elements("Child").DescendantNodes()  
    select node;  

foreach (XNode node in nodes)  
{  
    switch (node.NodeType)  
    {  
        case XmlNodeType.Element:  
            Console.WriteLine("Element: {0}", ((XElement)node).Name);  
            break;  
        case XmlNodeType.Text:  
            Console.WriteLine("Text: {0}", ((XText)node).Value);  
            break;  
        case XmlNodeType.Comment:  
            Console.WriteLine("Comment: {0}", ((XComment)node).Value);  
            break;  
        case XmlNodeType.ProcessingInstruction:  
            Console.WriteLine("PI: {0}", ((XProcessingInstruction)node).Data);  
            break;  
    }  
}  
Dim xmlTree As XElement = _  
<Root>  
    <Child>aaa<GrandChild anAttribute='xyz'>Text</GrandChild>  
        <!--a comment-->  
        <?xml-stylesheet type='text/xsl' href='test.xsl'?>  
    </Child>  
    <Child>ccc<GrandChild>Text</GrandChild>ddd</Child>  
</Root>  

Dim nodes As IEnumerable(Of XNode) = _  
    From node In xmlTree.<Child>.DescendantNodes _  
    Select node  

For Each node As XNode In nodes  
    Select Case node.NodeType  
        Case XmlNodeType.Element  
            Console.WriteLine("Element: {0}", DirectCast(node, XElement).Name)  
        Case XmlNodeType.Text  
            Console.WriteLine("Text: {0}", DirectCast(node, XText).Value)  
        Case XmlNodeType.Comment  
            Console.WriteLine("Comment: {0}", DirectCast(node, XComment).Value)  
        Case XmlNodeType.ProcessingInstruction  
            Console.WriteLine("PI: {0}", DirectCast(node, XProcessingInstruction).Data)  
    End Select  
Next  

この例を実行すると、次の出力が生成されます。This example produces the following output:

Text: aaa  
Element: GrandChild  
Text: Text  
Comment: a comment  
PI: type='text/xsl' href='test.xsl'  
Text: ccc  
Element: GrandChild  
Text: Text  
Text: ddd  

同じ例を次に示しますが、ここで XML が名前空間です。The following is the same example, but in this case the XML is in a namespace. 詳細については、次を参照してください。 XML 名前空間の使用します。For more information, see Working with XML Namespaces.

XNamespace aw = "http://www.adventure-works.com";  
XElement xmlTree = XElement.Parse(  
@"<Root xmlns='http://www.adventure-works.com'>  
    <Child>aaa<GrandChild anAttribute='xyz'>Text</GrandChild>  
        <!--a comment-->  
        <?xml-stylesheet type='text/xsl' href='test.xsl'?>  
    </Child>  
    <Child>ccc<GrandChild>Text</GrandChild>ddd</Child>  
</Root>");  
IEnumerable<XNode> nodes =  
    from node in xmlTree.Elements(aw + "Child").DescendantNodes()  
    select node;  

foreach (XNode node in nodes)  
{  
    switch (node.NodeType)  
    {  
        case XmlNodeType.Element:  
            Console.WriteLine("Element: {0}", ((XElement)node).Name);  
            break;  
        case XmlNodeType.Text:  
            Console.WriteLine("Text: {0}", ((XText)node).Value);  
            break;  
        case XmlNodeType.Comment:  
            Console.WriteLine("Comment: {0}", ((XComment)node).Value);  
            break;  
        case XmlNodeType.ProcessingInstruction:  
            Console.WriteLine("PI: {0}", ((XProcessingInstruction)node).Data);  
            break;  
    }  
}  
Imports <xmlns="http://www.adventure-works.com">  

Module Module1  
    Sub Main()  
        Dim xmlTree As XElement = _  
        <Root>  
            <Child>aaa<GrandChild anAttribute='xyz'>Text</GrandChild>  
                <!--a comment-->  
                <?xml-stylesheet type='text/xsl' href='test.xsl'?>  
            </Child>  
            <Child>ccc<GrandChild>Text</GrandChild>ddd</Child>  
        </Root>  

        Dim nodes As IEnumerable(Of XNode) = _  
            From node In xmlTree.<Child>.DescendantNodes _  
            Select node  

        For Each node As XNode In nodes  
            Select Case node.NodeType  
                Case XmlNodeType.Element  
                    Console.WriteLine("Element: {0}", DirectCast(node, XElement).Name)  
                Case XmlNodeType.Text  
                    Console.WriteLine("Text: {0}", DirectCast(node, XText).Value)  
                Case XmlNodeType.Comment  
                    Console.WriteLine("Comment: {0}", DirectCast(node, XComment).Value)  
                Case XmlNodeType.ProcessingInstruction  
                    Console.WriteLine("PI: {0}", DirectCast(node, XProcessingInstruction).Data)  
            End Select  
        Next  
    End Sub  
End Module  

この例を実行すると、次の出力が生成されます。This example produces the following output:

Text: aaa  
Element: {http://www.adventure-works.com}GrandChild  
Text: Text  
Comment: a comment  
PI: type='text/xsl' href='test.xsl'  
Text: ccc  
Element: {http://www.adventure-works.com}GrandChild  
Text: Text  
Text: ddd  

注釈

この軸の拡張メソッドが使用されるXDocumentXElementオブジェクト。This axis extension method is used on XDocument and XElement objects. 両方の型から派生してXContainerので、このメソッドによって操作、IEnumerable<T>XContainerソース コレクションを格納しています。Both of these types derive from XContainer, so this method operates on an IEnumerable<T> of XContainer that contains the source collection.

Visual Basic では、子孫要素の XML 統合軸いますはありません子孫のノードの軸は統合されたため、Visual Basic ユーザーはこの軸メソッドを明示的に使用する必要があります。Although Visual Basic has an integrated XML axis for descendant elements, there is no integrated axis for descendant nodes, so Visual Basic users must use this axis method explicitly.

このメソッドは遅延実行を使用します。This method uses deferred execution.

適用対象

こちらもご覧ください