PHP: formatting current date & time as: 2006-04-12 13:47:36 and substract 15 minutes

NaCo · 11-13-2008, 01:21 AM

Hello community,

I want to format PHP date and time to:

2006-04-12 13:47:36

and then substract 15 minutes, so the final result will be:

2006-04-12 13:32:36

So far I got this to format the current date & time:
$current_time=date("Y-n-j G:m:s");

But now I am stuck trying to figure out how to substract 15 minutes.

I will apreciate any help.

Thank you,

NACO.

NaCo · 11-13-2008, 02:27 AM

Bingo!

Here is the code to get what I needed:

Code:

<?php

//Right now date and time. Format: 2008-11-13 3:12:33
echo '<b>Date and Time when this page was fetched from server:</b><br>'.date("Y-n-j G:i:s");

//15 minutes ago date and time: Format:2008-11-13 2:57:33 
$past_time = date('Y-n-j G:i:s', mktime(date('G'),date('i')-15,date('s'), date('m'), date('d'), date('Y')));
echo '<br><br><b>The Date and Time 15 minutes before this page was fetched from server is:</b><br>'.$past_time;

?>

Hope this helps anyone who will need it.

Good luck!

sleddog · 11-13-2008, 04:42 AM

You could also use:

Code:

$past_time = date('Y-n-j G:i:s', time()-900);

NaCo · 11-13-2008, 10:19 AM

sleddog, yeap I think your way is easier.

It's all about Unix timestamp.

Interesting, very interesting.

thank you.

jlinkels · 11-13-2008, 07:31 PM

I have been writing a fairly large PHP application all about date and time, time intervals, schedules and whatnot. I can advise you to convert the time to timestamp as soon as it enters your program, do your arithmetic, and only for presentation purposes convert it back to date-time. Really, almost operations are easier done in timestamps.

You should also consider to write your entire program using UTC, system clock UTC, and at the very last moment, just before presentation convert it to UTC.

My company HQ is based in Europe UTC+1 and subject to daylight saving, I am located in UTC-4, no daylight saving. We transfer schedules regularly, and we have major schedule change in the night changing from summer to wintertime or vice versa. I can tell you, better use UTC.

jlinkels