Elements(T) Method (IEnumerable(T), XName)
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Extensions.Elements<T> Method (IEnumerable<T>, XName)

[ This article is for Windows Phone 8 developers. If you’re developing for Windows 10, see the latest documentation. ]

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)

public static IEnumerable<XElement> Elements<T>(
	this IEnumerable<T> source,
	XName name
)
where T : XContainer

Type Parameters

T

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

Parameters

source
Type: System.Collections.Generic.IEnumerable<T>
An IEnumerable<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<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.

Usage Note

In Visual Basic and C#, you can call this method as an instance method on any object of type IEnumerable<T>. When you use instance method syntax to call this method, omit the first parameter.

ExceptionCondition
ArgumentNullException

source is null.

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:


StringBuilder output = new StringBuilder();
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)
    output.Append(el + Environment.NewLine);

OutputTextBlock.Text = output.ToString();


Windows Phone OS

Supported in: 8.1, 8.0, 7.1, 7.0

Windows Phone

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