I have been trying unsuccessfully to extract text from inside a fairly simple XML document that includes names spaces using LibXML.

Previously I had been using XPATH and it worked a treat...but the parsing was just too slow. After writing to the author (Matt Seargent) he suggested that I use LibXML as in his words it was "much much faster"

However..my XPATH expressions no longer seemed to work. I solved part of this problem by declaring a namespace but have been unable to craft the XPATH expression needed to get the text I am after.

I have simplified the problem below maintaining all the important structural elements and am hoping someone might be able to throw me a bone as to what I am doing wrong.

Example XML and the source code I am using is below

I would appreciate any thoughts at this stage as myself and Mr Google have come up empty handed.

Regards

Steddy.


===========================
<?xml version="1.0" encoding="UTF-8"?>
<RootTag SchemaVersion="1.1" xmlns="http://www.wow.com/BlahML"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocati
+on="http://www.wow.com/BlahML BlahML1_1.xsd">

<MyTagA Tag="XXX">Some Text A</MyTagA>
<MyTagB Tag="XXX">Some Text A</MyTagB>

 <MiddleTag xsi:type="foo" magicvalue="wow">

    <MyImportantNode> xsi:type="foo" GeneralID="Random1" >
        <CannotGetTagA> YYYYYYYYYYY </CannotGetTagA>
        <CannotGetTagB> ZZZZZZZZZZZ  </CannotGetTagB>
    </MyImportantNode>
    <MyImportantNode> xsi:type="foo" GeneralID="Random2" >
        <CannotGetTagA> YYYYYYYYYY22 </CannotGetTagA>
        <CannotGetTagB> ZZZZZZZZZZ22  </CannotGetTagB>
    </MyImportantNode>
    <MyImportantNode> xsi:type="foo" GeneralID="Random3" >
        <CannotGetTagA> YYYYYYYYY333 </CannotGetTagA>
        <CannotGetTagB> ZZZZZZZZZ333  </CannotGetTagB>
    </MyImportantNode>

</MiddleTag>

</RootTag>
===========================

use strict;
use XML::LibXML;

my $version = "v0.1 - Dances with XML";
my $parser = XML::LibXML->new();

$parser->recover_silently(1);

my $doc = $parser->parse_file('test.xml'); #<-- The above XML

my $xpc = XML::LibXML::XPathContext->new($doc);
$xpc->registerNs(theNS => 'http://www.wow.com/BlahML');

my @MiddleNodeBits = $xpc->findnodes('//theNS:MiddleTag');

foreach my $nodeybits (@MiddleNodeBits) {
     # [1] Works but only gives me "Random1". Expected Random1,2 and 3
     print $nodeybits->findnodes('//@GeneralID')->string_value . "\n";

     # [2] Works...but gives me the entire XML once. Not very useful.
     print $nodeybits->findnodes('//*')->string_value . "\n";

     ##############################################
     # No output from lines below-Not sure why?
     ##############################################

     # [3]
     print $nodeybits->findnodes('//CannotGetTagA')->string_value . "\
+n";

     # [4]
     print $nodeybits->findnodes('/RootTag/MiddleTag[1]/MyImportantNod
+e[1]/CannotGetTagA[1]/text()')->string_value . "\n";

    # [5]
    print $nodeybits->findnodes('theNS:RootTag/MiddleTag[1]/MyImportan
+tNode[1]/CannotGetTagA[1]/text()')->string_value . "\n";

    # [6]
    print $nodeybits->findnodes('//RootTag/MiddleTag[1]/MyImportantNod
+e/CannotGetTagA/text()')->string_value . "\n";
          
}
exit(0);

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In reply to LibXML, Namespaces, xpath expression - This should be simple. by alittlebitdifferent

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