(C#) 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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Chilkat.Xml xml = new Chilkat.Xml();
Chilkat.Xml child = null;
Chilkat.Xml nextSibling = null;
Chilkat.Xml prevSibling = null;

bool success = xml.LoadXmlFile("qa_data/xml/fruit.xml");
if (success != true) {
    Debug.WriteLine(xml.LastErrorText);
    return;
}

// Iterate over the direct children by using FirstChild / NextSibling
child = xml.FirstChild();
bool bContinue = xml.LastMethodSuccess;
while ((bContinue == true)) {
    Debug.WriteLine(child.Tag + " : " + child.Content);
    nextSibling = child.NextSibling();
    bContinue = child.LastMethodSuccess;

    child = nextSibling;
}

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();
}

// 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;
}

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();
}

// Revert back up to the parent:
success = xml.GetParent2();