#!/usr/bin/perl -wT
use strict;
use CGI qw/:standard :cgi-lib *table/;

my $max_fields = 10; # Number of times to repeat fields
my $input = Vars;

if ($input->{'q'} eq 'save data') {
  open my $fh, '>>', 'data.txt';

  for (1 .. $max_fields) {
    next unless $input->{'title_' . $_}
      && $input->{'author_' . $_};
    print $fh
      "$input->{'title_' . $_}|$input->{'author_' . $_}\n";
  }

  close $fh;
}

print header(),
  start_html('My Data'),
    start_form(),
      start_table(),
        Tr(
          th( {align=>'left'}, 'Title' ),
          th( {align=>'left'}, 'Author' )
        );

print Tr(
  td( textfield( {name=>"title_$_",size=>30,force=>1} ) ),
  td( textfield( {name=>"author_$_",size=>30,force=>1} ) )
) for 1 .. $max_fields;

print Tr(
  th( {colspan=>2},
        submit( {name=>'q',value=>'save data'} )
  )
), end_table(), end_form(), end_html();