(VB.NET) Traverse Direct Children via FirstChild / NextSibling, or LastChild / PreviousSibling

Demonstrates some ways to iterate over direct child nodes using the FirstChild / NextSibling and LastChild / PreviousSibling methods.

The input XML, available at http://www.chilkatsoft.com/data/fruit.xml, is this:

<root>
    <fruit color="red">apple</fruit>
    <fruit color="green">pear</fruit>
    <veg color="orange">carrot</veg>
    <meat animal="cow">beef</meat>
    <xyz>
        <fruit color="blue">blueberry</fruit>
        <veg color="green">broccoli</veg>
    </xyz>
    <fruit color="purple">grape</fruit>
    <cheese color="yellow">cheddar</cheese>
</root>

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Dim xml As New Chilkat.Xml
Dim child As Chilkat.Xml
Dim nextSibling As Chilkat.Xml
Dim prevSibling As Chilkat.Xml

Dim success As Boolean = xml.LoadXmlFile("qa_data/xml/fruit.xml")
If (success <> True) Then
    Debug.WriteLine(xml.LastErrorText)
    Exit Sub
End If


' Iterate over the direct children by using FirstChild / NextSibling
child = xml.FirstChild()
Dim bContinue As Boolean = xml.LastMethodSuccess
While (bContinue = True)
    Debug.WriteLine(child.Tag & " : " & child.Content)
    nextSibling = child.NextSibling()
    bContinue = child.LastMethodSuccess

    child = nextSibling
End While
Debug.WriteLine("-----")

' Do the same, but with FirstChild2 / NextSibling2 to avoid
' creating so many XML object instances:
success = xml.FirstChild2()
While success = True
    Debug.WriteLine(xml.Tag & " : " & xml.Content)
    success = xml.NextSibling2()
End While
' Revert back up to the parent:
success = xml.GetParent2()

Debug.WriteLine("-----")

' Iterate in reverse order using LastChild / PreviousSibling
child = xml.LastChild()
bContinue = xml.LastMethodSuccess
While (bContinue = True)
    Debug.WriteLine(child.Tag & " : " & child.Content)
    prevSibling = child.PreviousSibling()
    bContinue = child.LastMethodSuccess

    child = prevSibling
End While
Debug.WriteLine("-----")

' Do the same, but with LastChild2 / PreviousSibling2 to avoid
' creating so many XML object instances:
success = xml.LastChild2()
While success = True
    Debug.WriteLine(xml.Tag & " : " & xml.Content)
    success = xml.PreviousSibling2()
End While
' Revert back up to the parent:
success = xml.GetParent2()