Extensions.Elements 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 the child elements of every element and document in the source collection.

Overloads

Name	Description
Elements<T>(IEnumerable<T>)	Returns a collection of the child elements of every element and document in the source collection.
Elements<T>(IEnumerable<T>, XName)	Returns a filtered collection of the child elements of every element and document in the source collection. Only elements that have a matching XName are included in the collection.

Remarks

Visual Basic contains an integrated elements axis that allows you to find all child elements with a specified XName for every element in the source collection.

This method uses deferred execution.

Elements<T>(IEnumerable<T>)

Source:: Extensions.cs

Source:: Extensions.cs

Source:: Extensions.cs

Source:: Extensions.cs

Source:: Extensions.cs

Returns a collection of the child elements of every element and document 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::XElement ^> ^ Elements(System::Collections::Generic::IEnumerable<T> ^ source);

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

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

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

<Extension()>
Public Function Elements(Of T As XContainer) (source As IEnumerable(Of T)) As IEnumerable(Of XElement)

Type Parameters

T

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

Parameters

source: IEnumerable<T>

An IEnumerable<T> of XElement that contains the source collection.

Returns

IEnumerable<XElement>

An IEnumerable<T> of XElement of the child elements of every element or document in the source collection.

Examples

The following example retrieves a collection of elements with the element name of Child. It then uses this axis method to retrieve all child elements of the collection.

XElement xmlTree = new XElement("Root",
    new XElement("Child",
        new XElement("GrandChild1", 1),
        new XElement("GrandChild2", 2)
    ),
    new XElement("Child",
        new XElement("GrandChild3", 3),
        new XElement("GrandChild4", 4)
    ),
    new XElement("Child",
        new XElement("GrandChild5", 5),
        new XElement("GrandChild6", 6)
    )
);

IEnumerable<XElement> allGrandChildren =
    from el in xmlTree.Elements("Child").Elements()
    select el;

foreach (XElement el in allGrandChildren)
    Console.WriteLine(el);

Dim xmlTree As XElement = _
     <Root>
          <Child>
              <GrandChild1>1</GrandChild1>
              <GrandChild2>2</GrandChild2>
          </Child>

          <Child>
              <GrandChild3>3</GrandChild3>
              <GrandChild4>4</GrandChild4>
          </Child>

          <Child>
              <GrandChild5>5</GrandChild5>
              <GrandChild6>6</GrandChild6>
          </Child>
      </Root>

Dim allGrandChildren = From el In xmlTree.<Child>.Elements _
                       Select el

For Each el As XElement In allGrandChildren
    Console.WriteLine(el)
Next

This example produces the following output:

<GrandChild1>1</GrandChild1>
<GrandChild2>2</GrandChild2>
<GrandChild3>3</GrandChild3>
<GrandChild4>4</GrandChild4>
<GrandChild5>5</GrandChild5>
<GrandChild6>6</GrandChild6>

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 + "Child",
        new XElement(aw + "GrandChild1", 1),
        new XElement(aw + "GrandChild2", 2)
    ),
    new XElement(aw + "Child",
        new XElement(aw + "GrandChild3", 3),
        new XElement(aw + "GrandChild4", 4)
    ),
    new XElement(aw + "Child",
        new XElement(aw + "GrandChild5", 5),
        new XElement(aw + "GrandChild6", 6)
    )
);

IEnumerable<XElement> allGrandChildren =
    from el in xmlTree.Elements(aw + "Child").Elements()
    select el;

foreach (XElement el in allGrandChildren)
    Console.WriteLine(el);

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

Module Module1
    Sub Main()
        Dim xmlTree As XElement = _
             <Root>
                 <Child>
                     <GrandChild1>1</GrandChild1>
                     <GrandChild2>2</GrandChild2>
                 </Child>

                 <Child>
                     <GrandChild3>3</GrandChild3>
                     <GrandChild4>4</GrandChild4>
                 </Child>

                 <Child>
                     <GrandChild5>5</GrandChild5>
                     <GrandChild6>6</GrandChild6>
                 </Child>
             </Root>

        Dim allGrandChildren = From el In xmlTree.<Child>.Elements _
                               Select el

        For Each el As XElement In allGrandChildren
            Console.WriteLine(el)
        Next
    End Sub
End Module

This example produces the following output:

<GrandChild1 xmlns="http://www.adventure-works.com">1</GrandChild1>
<GrandChild2 xmlns="http://www.adventure-works.com">2</GrandChild2>
<GrandChild3 xmlns="http://www.adventure-works.com">3</GrandChild3>
<GrandChild4 xmlns="http://www.adventure-works.com">4</GrandChild4>
<GrandChild5 xmlns="http://www.adventure-works.com">5</GrandChild5>
<GrandChild6 xmlns="http://www.adventure-works.com">6</GrandChild6>

Remarks

Although Visual Basic contains an integrated elements axis that allows you to find all child elements with a specified XName for every element in the source collection, there is no integrated elements axis that allows you to retrieve a collection of every child element for every element in the source collection.

This method uses deferred execution.

Applies to

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

Source:: Extensions.cs

Source:: Extensions.cs

Source:: Extensions.cs

Source:: Extensions.cs

Source:: Extensions.cs

Returns a filtered collection of the child elements of every element and document in the source collection. Only elements that have a matching XName are included in the collection.

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

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

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

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

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

Type Parameters

T

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

Parameters

source: IEnumerable<T>

An IEnumerable<T> of XElement that contains the source collection.

name: XName

The XName to match.

Returns

IEnumerable<XElement>

An IEnumerable<T> of XElement of the child elements of every element and document in the source collection. Only elements that have a matching XName are included in the collection.

Examples

This extension method is useful when you want to retrieve all elements with a specified name at a particular depth. This is easy if the document is very regular, but if the document is irregular, it can be a bit more difficult. In the following example, we want to retrieve all aaa elements that are children of Item elements. A given Item element may or may not contain an aaa element. This is easily accomplished using this extension method, as follows:

XElement xmlTree = new XElement("Root",
    new XElement("Item",
        new XElement("aaa", 1),
        new XElement("bbb", 2)
    ),
    new XElement("Item",
        new XElement("ccc", 3),
        new XElement("aaa", 4)
    ),
    new XElement("Item",
        new XElement("ddd", 5),
        new XElement("eee", 6)
    )
);

IEnumerable<XElement> allGrandChildren =
    from el in xmlTree.Elements("Item").Elements("aaa")
    select el;

foreach (XElement el in allGrandChildren)
    Console.WriteLine(el);

Dim xmlTree As XElement = _
    <Root>
        <Item>
            <aaa>1</aaa>
            <bbb>2</bbb>
        </Item>

        <Item>
            <ccc>3</ccc>
            <aaa>4</aaa>
        </Item>

        <Item>
            <ddd>5</ddd>
            <eee>6</eee>
        </Item>
    </Root>

Dim allGrandChildren = From el In xmlTree.<Item>.<aaa> _
                       Select el

For Each el As XElement In allGrandChildren
    Console.WriteLine(el)
Next

This example produces the following output:

<aaa>1</aaa>
<aaa>4</aaa>

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 + "Item",
        new XElement(aw + "aaa", 1),
        new XElement(aw + "bbb", 2)
    ),
    new XElement(aw + "Item",
        new XElement(aw + "ccc", 3),
        new XElement(aw + "aaa", 4)
    ),
    new XElement(aw + "Item",
        new XElement(aw + "ddd", 5),
        new XElement(aw + "eee", 6)
    )
);

IEnumerable<XElement> allGrandChildren =
    from el in xmlTree.Elements(aw + "Item").Elements(aw + "aaa")
    select el;

foreach (XElement el in allGrandChildren)
    Console.WriteLine(el);

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

Module Module1
    Sub Main()
        Dim xmlTree As XElement = _
            <Root>
                <Item>
                    <aaa>1</aaa>
                    <bbb>2</bbb>
                </Item>

                <Item>
                    <ccc>3</ccc>
                    <aaa>4</aaa>
                </Item>

                <Item>
                    <ddd>5</ddd>
                    <eee>6</eee>
                </Item>
            </Root>

        Dim allGrandChildren = From el In xmlTree.<Item>.<aaa> _
                               Select el

        For Each el As XElement In allGrandChildren
            Console.WriteLine(el)
        Next
    End Sub
End Module

This example produces the following output:

<aaa xmlns="http://www.adventure-works.com">1</aaa>
<aaa xmlns="http://www.adventure-works.com">4</aaa>

Remarks

Visual Basic users can use the integrated elements axis to retrieve the child elements of every element in a collection.

This method uses deferred execution.

Applies to

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Extensions.Elements Method

Definition

Overloads

Remarks

Elements<T>(IEnumerable<T>)

Type Parameters

Parameters

Returns

Examples

Remarks

See also

Applies to

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

Type Parameters

Parameters

Returns

Examples

Remarks

See also

Applies to