Compartilhar via

  • Artigo

XContainer.AddFirst Method

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Include Protected Members
Include Inherited Members

Include Silverlight Members
Include Silverlight for Windows Phone Members
Include XNA Framework Members

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

This member is overloaded. For complete information about this member, including syntax, usage, and examples, click a name in the overload list.

Overload List

  Name Description
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360 AddFirst(Object) Adds the specified content as the first children of this document or element.
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360 AddFirst(array<Object[]) Adds the specified content as the first children of this document or element.

Top

Remarks

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.

Examples

The following example creates two XML trees, and then uses this method to add the results of a query to one of them.

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>
                              <NewElement>Content</NewElement>
                          </Root>
xmlTree.AddFirst( _
    From el In srcTree.Elements _
    Where CInt(el) >= 3 _
    Select el)
output.Append(xmlTree)
output.Append(Environment.NewLine)


OutputTextBlock.Text = output.ToString()

StringBuilder output = new StringBuilder();
XElement srcTree = new XElement("Root",
    new XElement("Element1", 1),
    new XElement("Element2", 2),
    new XElement("Element3", 3),
    new XElement("Element4", 4),
    new XElement("Element5", 5)
);
XElement xmlTree = new XElement("Root",
    new XElement("NewElement", "Content")
);
xmlTree.AddFirst(
    from el in srcTree.Elements()
    where (int)el >= 3
    select el
);
output.Append(xmlTree  + Environment.NewLine);

OutputTextBlock.Text = output.ToString();