Extensions.Ancestors Method

Definition

Namespace:: System.Xml.Linq

Assemblies:: System.Xml.Linq.dll, System.Xml.XDocument.dll

Assemblies:: netstandard.dll, System.Xml.XDocument.dll

Assembly:: System.Xml.XDocument.dll

Assembly:: System.Xml.Linq.dll

Assembly:: netstandard.dll

Important

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Returns a collection of elements that contains the ancestors of every node in the source collection.

Overloads

Name	Description
Ancestors(IEnumerable)	Returns a collection of elements that contains the ancestors of every node in the source collection.
Ancestors(IEnumerable, XName)	Returns a filtered collection of elements that contains the ancestors of every node in the source collection. Only elements that have a matching XName are included in the collection.

Remarks

If multiple nodes in the source collection have the same ancestor, the ancestor will be included multiple times in the result collection. To avoid this, use the Distinct method.

This method uses deferred execution.

Ancestors(IEnumerable)

Source:: Extensions.cs

Source:: Extensions.cs

Source:: Extensions.cs

Source:: Extensions.cs

Source:: Extensions.cs

Returns a collection of elements that contains the ancestors of every node in the source collection.

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

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

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

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


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

Type Parameters

T

The type of the objects in source, constrained to XNode.

Parameters

source: IEnumerable

An IEnumerable of XNode that contains the source collection.

Returns

IEnumerable<XElement>

An IEnumerable of XElement that contains the ancestors of every node in the source collection.

Examples

The following example retrieves a collection of the great grandchildren elements. 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 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 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 = _
    
        
            
                content
            
        
        
            
                content
            
        
    

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

This example produces the following output:

Great Grand Children Elements
----
GreatGrandChild1
GreatGrandChild2

Ancestors
----
GrandChild1
Child1
Root
GrandChild2
Child2

The following is the same example, but in this case the XML is in a namespace. 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 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 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 

Module Module1
    Sub Main()
        Dim xmlTree As XElement = _
            
                
                    
                        content
                    
                
                
                    
                        content
                    
                
            

        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

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

Remarks

If multiple nodes in the source collection have the same ancestor, the ancestor will be included multiple times in the result collection. To avoid this, use the Distinct method.

This method uses deferred execution.

Applies to

Ancestors(IEnumerable, XName)

Source:: Extensions.cs

Source:: Extensions.cs

Source:: Extensions.cs

Source:: Extensions.cs

Source:: Extensions.cs

Returns a filtered collection of elements that contains the ancestors of every node in the source collection. Only elements that have a matching XName are included in the collection.

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

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

public static System.Collections.Generic.IEnumerable Ancestors(this System.Collections.Generic.IEnumerable 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 (requires 'T :> System.Xml.Linq.XNode)


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

Type Parameters

T

The type of the objects in source, constrained to XNode.

Parameters

source: IEnumerable

An IEnumerable of XNode that contains the source collection.

name: XName

The XName to match.

Returns

IEnumerable<XElement>

An IEnumerable of XElement that contains the ancestors of every node in the source collection. Only elements that have a matching XName are included in the collection.

Examples

The following example retrieves a collection of the great grandchildren elements. 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 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 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 = _
    
        
            
                content
            
        
        
            
                content
            
        
    

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

This example produces the following output:

Great Grand Children Elements
----
GreatGrandChild1
GreatGrandChild2

Ancestors
----
Child1

The following is the same example, but in this case the XML is in a namespace. 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 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 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 

Module Module1
    Sub Main()
        Dim xmlTree As XElement = _
            
                
                    
                        content
                    
                
                
                    
                        content
                    
                
            

        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

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

Remarks

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.

This method uses deferred execution.

Applies to

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Extensions.Ancestors Method

Definition

Overloads

Remarks

Ancestors(IEnumerable)

Type Parameters

Parameters

Returns

Examples

Remarks

See also

Applies to

Ancestors(IEnumerable, XName)

Type Parameters

Parameters

Returns

Examples

Remarks

See also

Applies to