my @tc = param("checkbox"); #like: 001.001 002.001 003.001 004.001

##</code><code>##

<exec>
    <tc id="001.100"></tc>
    <tc id="002.100"></tc>
    <tc id="003.100"></tc>
    <tc id="004.100"></tc>
</exec>

##</code><code>##

my $xml = new XML::Simple (Outputfile => $conf,
                           RootName=>'exec');
$exec = {
     'tc' => [
          {
            'id' => '001.001'
          },
          {
            'id' => '002.001'
          },
          {
            'id' => '003.001'
          },
      ]
 };

$data = $xml->XMLout($exec);
print Dumper($data);
}