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Extensions.Elements(Of T) Method (IEnumerable(Of 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.

Namespace:  System.Xml.Linq
Assembly:  System.Xml.Linq (in System.Xml.Linq.dll)

'Declaration
<ExtensionAttribute> _
Public Shared 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
Type: System.Collections.Generic.IEnumerable(Of T)

An IEnumerable(Of T) of XElement that contains the source collection.

name
Type: System.Xml.Linq.XName

The XName to match.

Return Value

Type: System.Collections.Generic.IEnumerable(Of XElement)
An IEnumerable(Of 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.

Usage Note

In Visual Basic and C#, you can call this method as an instance method on any object of type IEnumerable(Of T). When you use instance method syntax to call this method, omit the first parameter. For more information, see Extension Methods (Visual Basic) or Extension Methods (C# Programming Guide).

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.

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:

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 Working with XML Namespaces.

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>

.NET Framework

Supported in: 4.5.2, 4.5.1, 4.5, 4, 3.5

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Portable Class Library

Supported in: Portable Class Library

.NET for Windows Store apps

Supported in: Windows 8

.NET for Windows Phone apps

Supported in: Windows Phone 8.1, Windows Phone 8, Silverlight 8.1

Windows Phone 8.1, Windows Phone 8, Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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