(Visual FoxPro) 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>

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

LOCAL loXml
LOCAL loChild
LOCAL loNextSibling
LOCAL loPrevSibling
LOCAL lnSuccess
LOCAL lnBContinue

* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.Xml')
loXml = CreateObject('Chilkat.Xml')

lnSuccess = loXml.LoadXmlFile("qa_data/xml/fruit.xml")
IF (lnSuccess <> 1) THEN
    ? loXml.LastErrorText
    RELEASE loXml
    CANCEL
ENDIF

* Iterate over the direct children by using FirstChild / NextSibling
loChild = loXml.FirstChild()
lnBContinue = loXml.LastMethodSuccess
DO WHILE (lnBContinue = 1)
    ? loChild.Tag + " : " + loChild.Content
    loNextSibling = loChild.NextSibling()
    lnBContinue = loChild.LastMethodSuccess
    RELEASE loChild
    loChild = loNextSibling
ENDDO
? "-----"

* Do the same, but with FirstChild2 / NextSibling2 to avoid
* creating so many XML object instances:
lnSuccess = loXml.FirstChild2()
DO WHILE lnSuccess = 1
    ? loXml.Tag + " : " + loXml.Content
    lnSuccess = loXml.NextSibling2()
ENDDO
* Revert back up to the parent:
lnSuccess = loXml.GetParent2()

? "-----"

* Iterate in reverse order using LastChild / PreviousSibling
loChild = loXml.LastChild()
lnBContinue = loXml.LastMethodSuccess
DO WHILE (lnBContinue = 1)
    ? loChild.Tag + " : " + loChild.Content
    loPrevSibling = loChild.PreviousSibling()
    lnBContinue = loChild.LastMethodSuccess
    RELEASE loChild
    loChild = loPrevSibling
ENDDO
? "-----"

* Do the same, but with LastChild2 / PreviousSibling2 to avoid
* creating so many XML object instances:
lnSuccess = loXml.LastChild2()
DO WHILE lnSuccess = 1
    ? loXml.Tag + " : " + loXml.Content
    lnSuccess = loXml.PreviousSibling2()
ENDDO
* Revert back up to the parent:
lnSuccess = loXml.GetParent2()

RELEASE loXml