How can I extract values from the XML::Simple's data structure?

Question

I'm trying to figure out how to parse the <current></current> values from the first 2 (37% and 61.8F) in this XML. I can't figure it out since it seems that they have the same field names and are all under 'sensor'... any help would be appreciated...

Code in Perl:

#!/usr/bin/perl

use XML::Simple;
use Data::Dumper;
use LWP::Simple;


$url = 'http://localhostmachine/output/XML/output.xml';

# create object
my $xml = XML::Simple->new();

# read XML file
$data = $xml->XMLin(get($url));

# print output
print Dumper($data);

Output of XML file that I am reading in:

<?xml version="1.0" encoding="ISO-8859-1"?>
<?xml-stylesheet type="text/xsl" href="wpman.xsl"?>
<watchport>
<title>
<TxtTitle>Location#1</TxtTitle>
</title>
<sensor>
<type>Combo Sensor (Humidity)</type>
<name>ComboSensor000</name>
<status>OK</status>
<current>37%</current>
<high>42 (10/19/2009 @ 04:05PM)</high>
<low>28 (10/17/2009 @ 11:26AM)</low>
</sensor>
<sensor>
<type>Combo Sensor (Temperature)</type>
<name>ComboSensor000</name>
<status>OK</status>
<current>61.6F</current>
<high>65.8 (10/17/2009 @ 11:26AM)</high>
<low>60.1 (10/19/2009 @ 04:00PM)</low>
</sensor>
<sensor>
<type> </type>
<name> </name>
<status> </status>
<current> </current>
</sensor>
<sensor>
<type>Updated: 10/19/2009 @ 05:47 PM</type>
<name>(Updated every 2 minutes)</name>
<status> </status>
<current> </current>
</sensor>
</watchport>

Thanks so much!

Answer 1

I think this is what you want.

print $data->{sensor}[0]{current};
print $data->{sensor}[1]{current};

Answer 2

Since you've already got the answer, here are some links you might find helpful.

They give a good introduction to working with references and complex data structures, with plenty of examples.

• The Perl Data Structures Cookbook
• The References Tutorial.

I'm not trying to dismissively throw an RTFM at you, please don't take my response in that way. Perl has a lot of docs, it can be hard to find your way around them when starting out. How to RTFM is a good resource that helps demystify the manual.