Re: Finding node with attribute XML::LibXML

[ikegami]

Volume[@VolumeCategory="L"]

relative to the root of the document (/) means

/Volume[@VolumeCategory="L"]

They fail to find a match since there's no element named Volume at the root of the document.

/root/Volume[@VolumeCategory="L"]

would find the node in question, and so would its relative equivalent

root/Volume[@VolumeCategory="L"]

---

It's just like directories.

$ cd /

$ ls -d ikegami
ls: cannot access ikegami: No such file or directory

$ ls -d /ikegami
ls: cannot access /ikegami: No such file or directory

$ ls -d /home/ikegami
/home/ikegami

$ ls -d home/ikegami
home/ikegami

[jjap]

Thanks for the reply.

I did muff my example as I had been using getElementsByTagName which spared me the need to qualify the full path if may say.

Should I understand that that methods does not support attribute?

[ikegami]

If you want to search the whole document, you can use

/descendant::Volume[@VolumeCategory="L"]

which can be abbreviated to

//Volume[@VolumeCategory="L"]

Should I understand that that methods does not support attribute?

If you're asking if getElementsByTagName can filter the returned nodes to retain only those with a specific attribute value, then the answer is no. The only argument it takes is a tag name. You could do

my @matching =
   grep {
      my $vc = $_->getAttribute('VolumeCategory');
      defined($vc) && $vc eq "L"
   }
      $doc->getElementsByTagName('Volume');

but aforementioned

my @matching = $doc->findnodes('//Volume[@VolumeCategory="L"]');

is much simpler.

[Jim]

I think you meant to type…

/descendant::Volume[@VolumeCategory="L"]

With just one colon, you get…

XPath error : Undefined namespace prefix