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Use XML::Twig:

use strict;
use warnings;
use XML::Twig;

my $xmlStr = <<XML;
<?xml version="1.0" encoding="utf-8"?>
<result>
    <suites>
        <suite>
            <name>(Multiple_Sub_disp.xml)</name>
            <duration>2.0</duration>
            <cases>
                <case>
                    <duration>2.0</duration>
                    <className>Regression.CR0097956</className>
                    <testName>CR0097956_Multiple_Sub_disp</testName>
                    <skipped>false</skipped>
                    <failedSince>10</failedSince>
                </case>
            </cases>
        </suite>
        <suite>
            <name>(Multiple_Sub_mod.xml)</name>
            <duration>12.0</duration>
            <cases>
                <case>
                    <duration>12.0</duration>
                    <className>Regression.CR001000</className>
                    <testName>CR0097956_Multiple_Sub_mod</testName>
                    <skipped>false</skipped>
                    <failedSince>20</failedSince>
                </case>
            </cases>
        </suite>
        <suite>
            <name>(Single_Sub_create.xml)</name>
            <duration>12.0</duration>
            <cases>
                <case>
                    <duration>12.0</duration>
                    <className>Regression.CR002000</className>
                    <testName>CR0097956_Single_Sub_create</testName>
                    <skipped>false</skipped>
                    <failedSince>10</failedSince>
                </case>
            </cases>
        </suite>
    </suites>
    <duration>34082.0</duration>
</result>
XML

my $twig= XML::Twig->new(
    twig_handlers => { className => sub { print $_->text(), "\n" } }
);
$twig->parse($xmlStr);

__END__

Regression.CR0097956
Regression.CR001000
Regression.CR002000
[download]

I used XML::Tidy to neaten up your XML data.