How do I compare two DateTime objects in PHP 5.2.8?

user_73488 0
Viewed 386436

Having a look on the PHP documentation, the following two methods of the DateTime object would both seem to solve my problem:

Both these methods are marked in the doco as being available in version >= 5.3 (and, not surprisingly, if I try to call them I find they don't exist). I can't find any specific documentation for 5.2.8 so I am not sure if there are equivalent methods in my version. I have Googled the problem and found an eclectic range of solutions, none of which answer my very simple requirements:

  • How do I compare two DateTime objects?
  • Where can I find the doco for previous PHP versions? Specifically version 5.2.8?

For some context, I have the following code:

$st_dt = new DateTime(verifyParam ('start_date'));
$end_dt = new DateTime(verifyParam ('end_date'));

// is the end date more ancient than the start date?
if ($end_dt < $start_dt)

Apparently there is no comparison operator on this guy.

Edit

Apparently my assumptions were completely false (thanks Milen for illustrating this so effectively). There is a comparison operator and it works just fine thanks. Sometimes I really miss a compiler. The bug is in the code above, I am sure you will find it much faster than I did :).

datetime php
8 Answers

The following seems to confirm that there are comparison operators for the DateTime class:

dev:~# php
<?php
date_default_timezone_set('Europe/London');

$d1 = new DateTime('2008-08-03 14:52:10');
$d2 = new DateTime('2008-01-03 11:11:10');
var_dump($d1 == $d2);
var_dump($d1 > $d2);
var_dump($d1 < $d2);
?>
bool(false)
bool(true)
bool(false)
dev:~# php -v
PHP 5.2.6-1+lenny3 with Suhosin-Patch 0.9.6.2 (cli) (built: Apr 26 2009 20:09:03)
Copyright (c) 1997-2008 The PHP Group
Zend Engine v2.2.0, Copyright (c) 1998-2008 Zend Technologies
dev:~#
user_157850

If you want to compare dates and not time, you could use this:

$d1->format("Y-m-d") == $d2->format("Y-m-d")
user_24925360

You mentioned DateTime::diff to compare two dates, you can use it to get a more precise value than just a boolean.

For example the number of days:

$date1 = new DateTime('2021-07-09');
$date2 = new DateTime('2020-10-21');

echo $date1->diff($date2)->format('%R%a days');

But you could also use an alias of DateTime::diff which is date_diff (PHP 5 >= 5.3.0, PHP 7, PHP 8)

$date1 = new DateTime('2021-07-09');
$date2 = new DateTime('2020-10-21');

echo date_diff($date1, $date2)->format('%R%a days');
user_113501930
Related