(Ruby) 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>

Downloads for Windows/Linux and Install Instructions

require 'chilkat'

xml = Chilkat::CkXml.new()

#  The sample input XML is available at http://www.chilkatsoft.com/data/fruit.xml
success = xml.LoadXmlFile("fruit.xml")
if (success != true)
    print xml.lastErrorText() + "\n";
    exit
end

#  Iterate over the direct children by using FirstChild / NextSibling
# child is a CkXml
child = xml.FirstChild()
while !(child == nil )
    print child.tag() + " : " + child.content() + "\n";
    # nextSibling is a CkXml
    nextSibling = child.NextSibling()

    # child is a CkXml
    child = nextSibling
end
print "-----" + "\n";

#  Do the same, but with FirstChild2 / NextSibling2 to avoid
#  creating so many XML object instances:
success = xml.FirstChild2()
while success == true
    print xml.tag() + " : " + xml.content() + "\n";
    success = xml.NextSibling2()
end
#  Revert back up to the parent:
xml.GetParent2()

print "-----" + "\n";

#  Iterate in reverse order using LastChild / PreviousSibling
# child is a CkXml
child = xml.LastChild()
while !(child == nil )
    print child.tag() + " : " + child.content() + "\n";
    # prevSibling is a CkXml
    prevSibling = child.PreviousSibling()

    # child is a CkXml
    child = prevSibling
end
print "-----" + "\n";

#  Do the same, but with LastChild2 / PreviousSibling2 to avoid
#  creating so many XML object instances:
success = xml.LastChild2()
while success == true
    print xml.tag() + " : " + xml.content() + "\n";
    success = xml.PreviousSibling2()
end
#  Revert back up to the parent:
xml.GetParent2()