Date Function

Denise posted this at 15:15 — 7th October 2000.

They have: 19 posts

Joined: Oct 2000

Hi,

I still haven't resolved the basic authentication issue but have another problem.

I have one date eg: 10/3/00
I have an amount of days eg: 422

I need to be able to calculate the expiry date (date + days) and print it to screen in the above format ie: 15/5/01

Any ideas?

Denise

Vincent Puglia posted this at 20:04 — 7th October 2000.

They have: 634 posts

Joined: Dec 1999

Hi Denise,

Don't really remember the exact syntax, but in javascript something like:

var myMSec = myDate.getMilliseconds(); // myDate is 10/3/00 in date format
var myDaysinMSec = numOfDays * (60 * 60 * 24 * 1000)
var totalMsecs = myMSec + myDaysinMSec;
var newDate = setTime(totalMsecs);

I'll check later tonight, but if someone knows for certain, please slap me over the head and correct the code. Thanks
Vinny

Where the world once stood
the blades of grass cut me still

Denise posted this at 21:28 — 8th October 2000.

They have: 19 posts

Joined: Oct 2000

Hi Vincent,

Thanks for the tip but I eventually worked out a Perl sub routine. The only thing I'm stuck on now is displaying the date correctly. Well, I can bluff a way around it but was wondering whether anyone knew the easiest/proper way of displaying integers in two figures. ie: 1 to "01" and 2 to "02"?

Denise

Vincent Puglia posted this at 16:02 — 9th October 2000.

They have: 634 posts

Joined: Dec 1999

Hi Denise,

Do you mean something like:

if (x < 10) print("0",x)

BTW: my perl is shaky, so I'm hoping Ken will correct the syntax if it's wrong

vinny

Where the world once stood
the blades of grass cut me still

Rob Pengelly posted this at 16:29 — 9th October 2000.

They have: 850 posts

Joined: Jul 1999

I don't know of a 'proper' way to do it. But this would work:

$num="0$num",if(length($v)==1);

Denise posted this at 18:22 — 9th October 2000.

They have: 19 posts

Joined: Oct 2000

Thanks all,

I had:

if($day < 10) {$day = "0$day";}
if($month < 10) {$day = "0$month";}

So I think we're all in the same ball park!

Denise

japhy posted this at 21:19 — 17th October 2000.

They have: 161 posts

Joined: Dec 1999

If you want to do simple string formatting, use the sprintf() and printf() functions (borrowed from C, of course):

($day,$mon,$year) = (3,4,1982);
$date = sprintf "%02d/%02d/%4d", $mon, $day, $year;
print $date;  # 04/03/1982

Read perldoc -f sprintf and perldoc -f printf for information on those functions.

For date calculations, you should be safe in using the Time::Local module (it comes with Perl):

use Time::Local;
$now = '10/17/2000';
$plus_days = 500;
$future = add_days($now,$plus_days);
 
sub add_days {
  my ($date,$days) = @_;
  my ($m,$d,$y) = split '/', $date;
  my $time;
 
  $m--, $y -= 1900;  # $m is 9, $y is 100
  $time = timelocal(0,0,0,$d,$m,$y);
  $time += 86400 * $days;
  ($d,$m,$y) = (localtime($time))[3,4,5];
  return sprintf "%02d/%02d/%4d", $m+1, $d, $y+1900;
}

If you're doing more complex date computation, I highly suggest looking into the Date::Calc module, available on CPAN.

[Edited by japhy on 10-17-2000 at 05:21 PM]