my @array;
while ( my $line = <FILE> ) {
  if ( $line =~ /\<TAG\>(.*)\<\/TAG\>/ ) {
    push @array, $1;
  }
}

##</code><code>##

<TAG>data</TAG>
this is data to be stored

##</code><code>##

my @array;
while( my $line = <FILE> ) {
  if ( $line =~ /\<TAG\>data\<\/TAG\>/i ) {
    my $data_line = <FILE>;
    push @array, $data_line;
  }
}