Get time difference

Question

How can I compute time difference in PHP?

example: 2:00 and 3:30.

I want to convert the time to seconds then subtract them then convert it back to hours an

Answer 1

Look at the PHP DateTime object.

$dateA = new DateTime('2:00');
$dateB = new DateTime('3:00');

$difference = $dateA->diff($dateB);

(assuming you have >= PHP 5.3)

You can also do it the procedural way...

$dateA = strtotime('2:00');
$dateB = strtotime('3:00');

$difference = $dateB - $dateA;

See it on CodePad.org.

You can get the hour offset like so...

$hours = $difference / 3600;

If you are dealing with times that fall between a 24 hour period (0:00 - 23:59), you could also do...

$hours = (int) date('g', $difference);

Though that is probably too inflexible to be worth implementing.

Answer 2

Check this link ...

http://www.onlineconversion.com/days_between_advanced.htm

I used this to calculate the difference between server time and the users local time. Grab the hour difference and drop that in a form when the user is registering. I then use it to update the time on the site for the user when they do stuff online.

Once I got it working, I switched this line ...

if (form.date1.value == "")
    form.date1.value = s;

to ...

    form.date1.value = "<?PHP echo date("m/d/Y H:i:s", time()) ?>";

Now I can compare the user time and the server time! You can grab the seconds and mins as well.