'Usage

Dim instance As XElement
Dim writer As XmlWriter

instance.WriteTo(writer)

'Declaration

Public Overrides Sub WriteTo ( _
    writer As XmlWriter _
)

Dim sb As StringBuilder = New StringBuilder()
Dim xws As XmlWriterSettings = New XmlWriterSettings()
xws.OmitXmlDeclaration = True
xws.Indent = True

Using xw = XmlWriter.Create(sb, xws)
    xw.WriteStartElement("Root")
    Dim child1 As XElement = _
        <Child>
            <GrandChild>some content</GrandChild>
        </Child>
    child1.WriteTo(xw)
    Dim child2 As XElement = _ 
        <AnotherChild>
            <GrandChild>different content</GrandChild>
        </AnotherChild>
    child2.WriteTo(xw)
    xw.WriteEndElement()
End Using

Console.WriteLine(sb.ToString())