Extensions.Ancestors 方法

定義

命名空間:: System.Xml.Linq

組件:: System.Xml.XDocument.dll

組件:: System.Xml.Linq.dll

組件:: netstandard.dll

傳回包含來源集合中每個節點祖系的項目集合。Returns a collection of elements that contains the ancestors of every node in the source collection.

多載

Ancestors<T>(IEnumerable<T>)	傳回包含來源集合中每個節點祖系的項目集合。Returns a collection of elements that contains the ancestors of every node in the source collection.
Ancestors<T>(IEnumerable<T>, XName)	傳回包含來源集合中每個節點祖系的已篩選項目集合。Returns a filtered collection of elements that contains the ancestors of every node in the source collection. 集合中只會包含具有相符之 XName 的項目。Only elements that have a matching XName are included in the collection.

備註

如果來源集合中的多個節點具有相同的上階，則會在結果集合中多次包含上階。If multiple nodes in the source collection have the same ancestor, the ancestor will be included multiple times in the result collection. 若要避免這種情況，請使用 Distinct 方法。To avoid this, use the Distinct method.

這個方法會使用延後的執行。This method uses deferred execution.

Ancestors<T>(IEnumerable<T>)

傳回包含來源集合中每個節點祖系的項目集合。Returns a collection of elements that contains the ancestors of every node in the source collection.

public:
generic <typename T>
 where T : System::Xml::Linq::XNode[System::Runtime::CompilerServices::Extension]
 static System::Collections::Generic::IEnumerable<System::Xml::Linq::XElement ^> ^ Ancestors(System::Collections::Generic::IEnumerable<T> ^ source);

public static System.Collections.Generic.IEnumerable<System.Xml.Linq.XElement> Ancestors<T> (this System.Collections.Generic.IEnumerable<T> source) where T : System.Xml.Linq.XNode;

public static System.Collections.Generic.IEnumerable<System.Xml.Linq.XElement> Ancestors<T> (this System.Collections.Generic.IEnumerable<T>? source) where T : System.Xml.Linq.XNode;

static member Ancestors : seq<'T (requires 'T :> System.Xml.Linq.XNode)> -> seq<System.Xml.Linq.XElement> (requires 'T :> System.Xml.Linq.XNode)

<Extension()>
Public Function Ancestors(Of T As XNode) (source As IEnumerable(Of T)) As IEnumerable(Of XElement)

類型參數

T

source 中物件的型別，限制為 XNode。The type of the objects in source, constrained to XNode.

參數

source: IEnumerable<T>

IEnumerable<T> 的 XNode，其中包含來源集合。An IEnumerable<T> of XNode that contains the source collection.

傳回

IEnumerable<XElement>

IEnumerable<T> 的 XElement，其中包含來源集合中每個節點的祖系。An IEnumerable<T> of XElement that contains the ancestors of every node in the source collection.

範例

下列範例會捕獲絕佳孫系元素的集合。The following example retrieves a collection of the great grandchildren elements. 然後，它會使用這個 axis 方法來抓取集合中所有專案的上階。It then uses this axis method to retrieve all ancestors of all elements in the collection.

XElement xmlTree = new XElement("Root",  
    new XElement("Child1",  
        new XElement("GrandChild1",  
            new XElement("GreatGrandChild1", "content")  
        )  
    ),  
    new XElement("Child2",  
        new XElement("GrandChild2",  
            new XElement("GreatGrandChild2", "content")  
        )  
    )  
);  
IEnumerable<XElement> greatGrandChildren =  
    from el in xmlTree.Descendants()  
    where el.Name.LocalName.StartsWith("Great")  
    select el;  

Console.WriteLine("Great Grand Children Elements");  
Console.WriteLine("----");  
foreach (XElement de in greatGrandChildren)  
    Console.WriteLine(de.Name);  

IEnumerable<XElement> allAncestors =  
    from el in greatGrandChildren.Ancestors().Distinct()  
    select el;  

Console.WriteLine("");  
Console.WriteLine("Ancestors");  
Console.WriteLine("----");  
foreach (XElement de in allAncestors)  
    Console.WriteLine(de.Name);

Dim xmlTree As XElement = _  
    <Root>  
        <Child1>  
            <GrandChild1>  
                <GreatGrandChild1>content</GreatGrandChild1>  
            </GrandChild1>  
        </Child1>  
        <Child2>  
            <GrandChild2>  
                <GreatGrandChild2>content</GreatGrandChild2>  
            </GrandChild2>  
        </Child2>  
    </Root>  

Dim greatGrandChildren = From el In xmlTree.Descendants _  
                         Where el.Name.LocalName.StartsWith("Great") _  
                         Select el  

Console.WriteLine("Great Grand Children Elements")  
Console.WriteLine("----")  

For Each de As XElement In greatGrandChildren  
    Console.WriteLine(de.Name)  
Next  

Dim allAncestors = From el In greatGrandChildren.Ancestors.Distinct _  
                   Select el  

Console.WriteLine("")  
Console.WriteLine("Ancestors")  
Console.WriteLine("----")  

For Each de As XElement In allAncestors  
    Console.WriteLine(de.Name)  
Next

這個範例會產生下列輸出：This example produces the following output:

Great Grand Children Elements  
----  
GreatGrandChild1  
GreatGrandChild2  

Ancestors  
----  
GrandChild1  
Child1  
Root  
GrandChild2  
Child2

以下是相同的範例，但在此情況下，XML 會在命名空間中。The following is the same example, but in this case the XML is in a namespace. 如需詳細資訊，請參閱使用 XML 命名空間。For more information, see Work with XML Namespaces.

XNamespace aw = "http://www.adventure-works.com";  
XElement xmlTree = new XElement(aw + "Root",  
    new XElement(aw + "Child1",  
        new XElement(aw + "GrandChild1",  
            new XElement(aw + "GreatGrandChild1", "content")  
        )  
    ),  
    new XElement(aw + "Child2",  
        new XElement(aw + "GrandChild2",  
            new XElement(aw + "GreatGrandChild2", "content")  
        )  
    )  
);  
IEnumerable<XElement> greatGrandChildren =  
    from el in xmlTree.Descendants()  
    where el.Name.LocalName.StartsWith("Great")  
    select el;  

Console.WriteLine("Great Grand Children Elements");  
Console.WriteLine("----");  
foreach (XElement de in greatGrandChildren)  
    Console.WriteLine(de.Name);  

IEnumerable<XElement> allAncestors =  
    from el in greatGrandChildren.Ancestors().Distinct()  
    select el;  

Console.WriteLine("");  
Console.WriteLine("Ancestors");  
Console.WriteLine("----");  
foreach (XElement de in allAncestors)  
    Console.WriteLine(de.Name);

Imports <xmlns="http://www.adventure-works.com">  

Module Module1  
    Sub Main()  
        Dim xmlTree As XElement = _  
            <Root>  
                <Child1>  
                    <GrandChild1>  
                        <GreatGrandChild1>content</GreatGrandChild1>  
                    </GrandChild1>  
                </Child1>  
                <Child2>  
                    <GrandChild2>  
                        <GreatGrandChild2>content</GreatGrandChild2>  
                    </GrandChild2>  
                </Child2>  
            </Root>  

        Dim greatGrandChildren = From el In xmlTree.Descendants _  
                                 Where el.Name.LocalName.StartsWith("Great") _  
                                 Select el  

        Console.WriteLine("Great Grand Children Elements")  
        Console.WriteLine("----")  

        For Each de As XElement In greatGrandChildren  
            Console.WriteLine(de.Name)  
        Next  

        Dim allAncestors = From el In greatGrandChildren.Ancestors.Distinct _  
                           Select el  

        Console.WriteLine("")  
        Console.WriteLine("Ancestors")  
        Console.WriteLine("----")  

        For Each de As XElement In allAncestors  
            Console.WriteLine(de.Name)  
        Next  
    End Sub  
End Module

這個範例會產生下列輸出：This example produces the following output:

Great Grand Children Elements  
----  
{http://www.adventure-works.com}GreatGrandChild1  
{http://www.adventure-works.com}GreatGrandChild2  

Ancestors  
----  
{http://www.adventure-works.com}GrandChild1  
{http://www.adventure-works.com}Child1  
{http://www.adventure-works.com}Root  
{http://www.adventure-works.com}GrandChild2  
{http://www.adventure-works.com}Child2

備註

這個方法會使用延後的執行。This method uses deferred execution.

另請參閱

適用於

Ancestors<T>(IEnumerable<T>, XName)

傳回包含來源集合中每個節點祖系的已篩選項目集合。Returns a filtered collection of elements that contains the ancestors of every node in the source collection. 集合中只會包含具有相符之 XName 的項目。Only elements that have a matching XName are included in the collection.

public:
generic <typename T>
 where T : System::Xml::Linq::XNode[System::Runtime::CompilerServices::Extension]
 static System::Collections::Generic::IEnumerable<System::Xml::Linq::XElement ^> ^ Ancestors(System::Collections::Generic::IEnumerable<T> ^ source, System::Xml::Linq::XName ^ name);

public static System.Collections.Generic.IEnumerable<System.Xml.Linq.XElement> Ancestors<T> (this System.Collections.Generic.IEnumerable<T> source, System.Xml.Linq.XName name) where T : System.Xml.Linq.XNode;

public static System.Collections.Generic.IEnumerable<System.Xml.Linq.XElement> Ancestors<T> (this System.Collections.Generic.IEnumerable<T>? source, System.Xml.Linq.XName? name) where T : System.Xml.Linq.XNode;

static member Ancestors : seq<'T (requires 'T :> System.Xml.Linq.XNode)> * System.Xml.Linq.XName -> seq<System.Xml.Linq.XElement> (requires 'T :> System.Xml.Linq.XNode)

<Extension()>
Public Function Ancestors(Of T As XNode) (source As IEnumerable(Of T), name As XName) As IEnumerable(Of XElement)

類型參數

T

source 中物件的型別，限制為 XNode。The type of the objects in source, constrained to XNode.

參數

source: IEnumerable<T>

IEnumerable<T> 的 XNode，其中包含來源集合。An IEnumerable<T> of XNode that contains the source collection.

name: XName

要比對的 XName。The XName to match.

傳回

IEnumerable<XElement>

IEnumerable<T> 的 XElement，其中包含來源集合中每個節點的祖系。An IEnumerable<T> of XElement that contains the ancestors of every node in the source collection. 集合中只會包含具有相符之 XName 的項目。Only elements that have a matching XName are included in the collection.

範例

下列範例會捕獲絕佳孫系元素的集合。The following example retrieves a collection of the great grandchildren elements. 然後，它會使用這個 axis 方法來抓取集合中所有符合指定之元素的上階 XName 。It then uses this axis method to retrieve all ancestors of all elements in the collection that match a specified XName.

XElement xmlTree = new XElement("Root",  
    new XElement("Child1",  
        new XElement("GrandChild1",  
            new XElement("GreatGrandChild1", "content")  
        )  
    ),  
    new XElement("Child2",  
        new XElement("GrandChild2",  
            new XElement("GreatGrandChild2", "content")  
        )  
    )  
);  
IEnumerable<XElement> greatGrandChildren =  
    from el in xmlTree.Descendants()  
    where el.Name.LocalName.StartsWith("Great")  
    select el;  

Console.WriteLine("Great Grand Children Elements");  
Console.WriteLine("----");  
foreach (XElement de in greatGrandChildren)  
    Console.WriteLine(de.Name);  

IEnumerable<XElement> allAncestors =  
    from el in greatGrandChildren.Ancestors("Child1")  
    select el;  

Console.WriteLine("");  
Console.WriteLine("Ancestors");  
Console.WriteLine("----");  
foreach (XElement de in allAncestors)  
    Console.WriteLine(de.Name);

Dim xmlTree As XElement = _  
    <Root>  
        <Child1>  
            <GrandChild1>  
                <GreatGrandChild1>content</GreatGrandChild1>  
            </GrandChild1>  
        </Child1>  
        <Child2>  
            <GrandChild2>  
                <GreatGrandChild2>content</GreatGrandChild2>  
            </GrandChild2>  
        </Child2>  
    </Root>  

Dim greatGrandChildren = From el In xmlTree.Descendants _  
                         Where el.Name.LocalName.StartsWith("Great") _  
                         Select el  

Console.WriteLine("Great Grand Children Elements")  
Console.WriteLine("----")  

For Each de As XElement In greatGrandChildren  
    Console.WriteLine(de.Name)  
Next  

Dim allAncestors = From el In greatGrandChildren.Ancestors("Child1") _  
                   Select el  

Console.WriteLine("")  
Console.WriteLine("Ancestors")  
Console.WriteLine("----")  

For Each de As XElement In allAncestors  
    Console.WriteLine(de.Name)  
Next

這個範例會產生下列輸出：This example produces the following output:

Great Grand Children Elements  
----  
GreatGrandChild1  
GreatGrandChild2  

Ancestors  
----  
Child1

XNamespace aw = "http://www.adventure-works.com";  
XElement xmlTree = new XElement(aw + "Root",  
    new XElement(aw + "Child1",  
        new XElement(aw + "GrandChild1",  
            new XElement(aw + "GreatGrandChild1", "content")  
        )  
    ),  
    new XElement(aw + "Child2",  
        new XElement(aw + "GrandChild2",  
            new XElement(aw + "GreatGrandChild2", "content")  
        )  
    )  
);  
IEnumerable<XElement> greatGrandChildren =  
    from el in xmlTree.Descendants()  
    where el.Name.LocalName.StartsWith("Great")  
    select el;  

Console.WriteLine("Great Grand Children Elements");  
Console.WriteLine("----");  
foreach (XElement de in greatGrandChildren)  
    Console.WriteLine(de.Name);  

IEnumerable<XElement> allAncestors =  
    from el in greatGrandChildren.Ancestors(aw + "Child1")  
    select el;  

Console.WriteLine("");  
Console.WriteLine("Ancestors");  
Console.WriteLine("----");  
foreach (XElement de in allAncestors)  
    Console.WriteLine(de.Name);

Imports <xmlns="http://www.adventure-works.com">  

Module Module1  
    Sub Main()  
        Dim xmlTree As XElement = _  
            <Root>  
                <Child1>  
                    <GrandChild1>  
                        <GreatGrandChild1>content</GreatGrandChild1>  
                    </GrandChild1>  
                </Child1>  
                <Child2>  
                    <GrandChild2>  
                        <GreatGrandChild2>content</GreatGrandChild2>  
                    </GrandChild2>  
                </Child2>  
            </Root>  

        Dim greatGrandChildren = From el In xmlTree.Descendants _  
                                 Where el.Name.LocalName.StartsWith("Great") _  
                                 Select el  

        Console.WriteLine("Great Grand Children Elements")  
        Console.WriteLine("----")  

        For Each de As XElement In greatGrandChildren  
            Console.WriteLine(de.Name)  
        Next  

        Dim allAncestors = From el In greatGrandChildren.Ancestors(GetXmlNamespace() + "Child1") _  
                           Select el  

        Console.WriteLine("")  
        Console.WriteLine("Ancestors")  
        Console.WriteLine("----")  

        For Each de As XElement In allAncestors  
            Console.WriteLine(de.Name)  
        Next  
    End Sub  
End Module

這個範例會產生下列輸出：This example produces the following output:

Great Grand Children Elements  
----  
{http://www.adventure-works.com}GreatGrandChild1  
{http://www.adventure-works.com}GreatGrandChild2  

Ancestors  
----  
{http://www.adventure-works.com}Child1

備註

如果來源集合中有多個節點的上階具有相同的 XName 上階，則上階將會在結果集合中包含多次。If multiple nodes in the source collection have the same ancestor with a matching XName, the ancestor will be included multiple times in the result collection.

這個方法會使用延後的執行。This method uses deferred execution.

另請參閱

適用於

Extensions.Ancestors 方法

定義

多載

備註

Ancestors<T>(IEnumerable<T>)

類型參數

參數

傳回

範例

備註

另請參閱

適用於

Ancestors<T>(IEnumerable<T>, XName)

類型參數

參數

傳回

範例

備註

另請參閱

適用於

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