AddFirst Method (Object)
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XContainer.AddFirst Method (Object)

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

Adds the specified content as the first children of this document or element.

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

'Declaration
Public Sub AddFirst ( _
	content As Object _
)

Parameters

content
Type: System.Object
A content object containing simple content or a collection of content objects to be added.

This method adds the new content before the existing content of the XContainer.

For details about the valid content that can be passed to this function, see Valid Content of XElement and XDocument Objects.

This method will raise the Changed and the Changing events.

The following example creates two XML trees, uses this method to add an XElement object as the first element to one of them. It also adds the results of a LINQ query to the XML tree.


Dim output As New StringBuilder
Dim srcTree As XElement = _
        <Root>
            <Element1>1</Element1>
            <Element2>2</Element2>
            <Element3>3</Element3>
            <Element4>4</Element4>
            <Element5>5</Element5>
        </Root>

Dim xmlTree As XElement = _
        <Root>
            <Child1>1</Child1>
            <Child2>2</Child2>
            <Child3>3</Child3>
            <Child4>4</Child4>
            <Child5>5</Child5>
        </Root>

xmlTree.AddFirst(New XElement("NewChild", "new content"))
xmlTree.AddFirst( _
    From el In srcTree.Elements() _
    Where CInt(el) > 3 _
    Select el _
)
' Even though Child9 does not exist in srcTree, the following statement will not
' throw an exception, and nothing will be added to xmlTree
xmlTree.AddFirst(srcTree.<Child9>)
output.Append(xmlTree)
output.Append(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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