Help when paging through sets of results
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README

NAME
    Data::Page - help when paging through sets of results

SYNOPSIS
      use Data::Page;

      my $page = Data::Page->new();
      $page->total_entries($total_entries);
      $page->entries_per_page($entries_per_page);
      $page->current_page($current_page);

      print "         First page: ", $page->first_page, "\n";
      print "          Last page: ", $page->last_page, "\n";
      print "First entry on page: ", $page->first, "\n";
      print " Last entry on page: ", $page->last, "\n";

DESCRIPTION
    When searching through large amounts of data, it is often the case that
    a result set is returned that is larger than we want to display on one
    page. This results in wanting to page through various pages of data. The
    maths behind this is unfortunately fiddly, hence this module.

    The main concept is that you pass in the number of total entries, the
    number of entries per page, and the current page number. You can then
    call methods to find out how many pages of information there are, and
    what number the first and last entries on the current page really are.

    For example, say we wished to page through the integers from 1 to 100
    with 20 entries per page. The first page would consist of 1-20, the
    second page from 21-40, the third page from 41-60, the fourth page from
    61-80 and the fifth page from 81-100. This module would help you work
    this out.

METHODS
  new
    This is the constructor, which takes no arguments.

      my $page = Data::Page->new();

    There is also an old, deprecated constructor, which currently takes two
    mandatory arguments, the total number of entries and the number of
    entries per page. It also optionally takes the current page number:

      my $page = Data::Page->new($total_entries, $entries_per_page, $current_page);

  total_entries
    This method get or sets the total number of entries:

      print "Entries:", $page->total_entries, "\n";

  entries_per_page
    This method gets or sets the total number of entries per page (which
    defaults to 10):

      print "Per page:", $page->entries_per_page, "\n";

  current_page
    This method gets or sets the current page number (which defaults to 1):

      print "Page: ", $page->current_page, "\n";

  entries_on_this_page
    This methods returns the number of entries on the current page:

      print "There are ", $page->entries_on_this_page, " entries displayed\n";

  first_page
    This method returns the first page. This is put in for reasons of
    symmetry with last_page, as it always returns 1:

      print "Pages range from: ", $page->first_page, "\n";

  last_page
    This method returns the total number of pages of information:

      print "Pages range to: ", $page->last_page, "\n";

  first
    This method returns the number of the first entry on the current page:

      print "Showing entries from: ", $page->first, "\n";

  last
    This method returns the number of the last entry on the current page:

      print "Showing entries to: ", $page->last, "\n";

  previous_page
    This method returns the previous page number, if one exists. Otherwise
    it returns undefined:

      if ($page->previous_page) {
        print "Previous page number: ", $page->previous_page, "\n";
      }

  next_page
    This method returns the next page number, if one exists. Otherwise it
    returns undefined:

      if ($page->next_page) {
        print "Next page number: ", $page->next_page, "\n";
      }

  splice
    This method takes in a listref, and returns only the values which are on
    the current page:

      @visible_holidays = $page->splice(\@holidays);

  skipped
    This method is useful paging through data in a database using SQL LIMIT
    clauses. It is simply $page->first - 1:

      $sth = $dbh->prepare(
        q{SELECT * FROM table ORDER BY rec_date LIMIT ?, ?}
      );
      $sth->execute($date, $page->skipped, $page->entries_per_page);

NOTES
    It has been said before that this code is "too simple" for CPAN, but I
    must disagree. I have seen people write this kind of code over and over
    again and they always get it wrong. Perhaps now they will spend more
    time getting the rest of their code right...

SEE ALSO
    Related modules which may be of interest: Data::Pageset,
    Data::Page::Tied, Data::SpreadPagination.

AUTHOR
    Based on code originally by Leo Lapworth, with many changes added by by
    Leon Brocard <acme@astray.com>.

COPYRIGHT
    Copyright (C) 2000-8, Leon Brocard

LICENSE
    This module is free software; you can redistribute it or modify it under
    the same terms as Perl itself.