How do I convert date format between 'DD-MM-YYYY' and 'YYYY-MM-DD' back & forth?

naikonta has asked for the wisdom of the Perl Monks concerning the following question: ⭐ (dates and times)

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Re: How do I convert date format between 'DD-MM-YYYY' and 'YYYY-MM-DD' back & forth?⭐ by jettero (Monsignor) on May 08, 2007 at 19:41 UTC
use Date::Manip: `my $date = UnixDate( ParseDate($thingy), '%Y-%m-%d' );` [download]	[reply] [d/l]
Re: How do I convert date format between 'DD-MM-YYYY' and 'YYYY-MM-DD' back & forth? by naikonta (Curate) on May 08, 2007 at 19:35 UTC
Well, basically, just reverse the date components in the list and put it back as string. `my $in_date = '30-04-2007'; my $db_date = join '-', reverse split '-', $in_date; # to get the original format, do the same thing my $pr_date = join '-', reverse split '-', $db_date; print "in: $in_date; db: $db_date; pr: $pr_date\n"; # in: 30-04-2007; db: 2007-04-30; pr: 30-04-2007` [download] For multi-possible-separator, use the non-digit character class for `split()`. `my $in_date = '02/05/2007'; # or 02.05.2007, or any non-digit-separato +rs my $db_date = join '-', reverse split /\D/, $in_date; # to get the original format, do the same thing as before my $sep = '-'; my $pr_date = join $sep, reverse split '-', $db_date; print "in: $in_date; db: $db_date; pr: $pr_date\n"; # in: 02/05/2007; db: 2007-05-02; pr: 02-05-2007` [download] In this situation, there's no way to convert the date back with its original separator unless you kept it somewhere somehow, if that really matters. Besides, this might be a good chance to enforce your standard separator :-)	[reply] [d/l] [select]
Re: How do I convert date format between 'DD-MM-YYYY' and 'YYYY-MM-DD' back & forth? by naikonta (Curate) on May 08, 2007 at 19:39 UTC
The following answer uses regexes. `# UK-style my $in_date = '30-04-2007'; (my $db_date = $in_date) =~ s/(\d\d)-(\d\d)-(\d\d\d\d)/$3-$2-$1/; (my $pr_date = $db_date) =~ s/(\d\d\d\d)-(\d\d)-(\d\d)/$3-$2-$1/; print "in: $in_date; db: $db_date; pr: $pr_date\n"; # in: 30-04-2007; db: 2007-04-30; pr: 30-04-2007` [download] `# US-style my $in_date = '05-14-2007'; (my $db_date = $in_date) =~ s/(\d\d)-(\d\d)-(\d\d\d\d)/$3-$1-$2/; (my $pr_date = $db_date) =~ s/(\d\d\d\d)-(\d\d)-(\d\d)/$2-$3-$1/; print "in: $in_date; db: $db_date; pr: $pr_date\n"; # in: 05-14-2007; db: 2007-05-14; pr: 05-14-2007` [download] Instead of rolling your own, some CPAN modules might help, such as Date::Tiny, Date::Formatter, or Date::Simple. They look promising but I haven't tried them myself.	[reply] [d/l] [select]
Re: How do I convert date format between 'DD-MM-YYYY' and 'YYYY-MM-DD' back & forth? by naikonta (Curate) on May 08, 2007 at 19:36 UTC
Just in case you specify that the date must be in US-style (MM-DD-YYYY), then the above split won't work. `my $in_date = '11-24-2007'; # or 11/24/2007, or 11.24.2007, or any non +-digit-separators my @parts = split /\D/, $in_date; my $db_date = join '-', @parts[2, 0, 1]; # to get the original format: my $sep = '-'; my @parts = split $sep, $db_date; my $pr_date = join $sep, @parts[1, 2, 0]; print "in: $in_date; db: $db_date; pr: $pr_date\n"; # in: 11-24-2007; db: 2007-11-24; pr: 11-24-2007` [download]	[reply] [d/l]