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

my $str = <<EOF;
<?xml version="1.0" encoding="UTF-8"?>
<Header>
    <Main id="1" name="Item1">
    </Main>
    <Main id="2" name="Item2">
    </Main>
    <!--Main id="3" name="Item4">
    </Main-->
    <Main id="4" name="Item5">
    </Main>
</Header>
EOF

my $t = XML::Twig->new(twig_handlers => { 
    Main => sub {print $_->att('id'), "\n"}
});
$t->parse($str);

__END__

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