DateInterval add possibility to have the result in hours, minutes, seconds

[devbysb]

Hi,

is it possible to have the result of a DateInterval in numbers of hours, minutes, seconds like this

Example you have a DateInterval with 48hours

(\DateInterval::createFromDateString('2 days'))->h  // result 0 
(\DateInterval::createFromDateString('2 days'))->totalHours  // result 48
(\DateInterval::createFromDateString('2 days'))->totalMinutes // result 2880
(\DateInterval::createFromDateString('2 days'))->totalSeconds // result 172800

because if I do calculations on working hours for example it's easier for users to understand 48h00 instead of 2days 00h 00minutes and if I have to redo calculations and I need the hours, I have to reconvert the 2 days in hours and add them to the hours...

[heiglandreas]

That's not really feasible. Are those 2 days during a DST transition? then it'd be 47 hours. Or 49? 😉

You would definitely need a time-reference to be accurate about that.

And that then also causes the same implications for minutes and seconds. Oh: And what about leap-seconds? 😉

[devbysb]

Hi, sorry but I have difficulty understanding an interval of 2 days, will it always be 48 hours whatever the country?
I agree that the difference between 2 dates depends on the time zones but once we have this interval whether it is in days, in hours or in minutes it remains the same it is just the "unit" which changes.

I may have expressed myself badly, what interests me is being able to convert the result of a dateInterval into a total of hours or a total of minutes or a total of seconds.

[leesherwood]

@devbysb

Essentially what you're asking for is something like this?

$totalHours = ($dateInterval->d * 24) + $dateInterval->h;

Let's make that a function:

function DateIntervalTotalHours(DateInterval $di) {
	return ($di->d * 24) + $di->h;
}

And run:

var_dump(DateIntervalTotalHours(DateInterval::createFromDateString('2 days')));

// Output: 48

Great, exactly what you wanted? How hard was that?!

Now I come along, I want to make use of this totalHours property:

$ukA = new DateTime('2024-10-27T00:00:00', new DateTimeZone('Europe/London'));
$ukB = new DateTime('2024-10-29T00:00:00', new DateTimeZone('Europe/London'));
var_dump(DateIntervalTotalHours($ukB->diff($ukA)));

// Output: 48

Awesome. I'll charge my customer for 48 hours of my service.

But wait, let's check the diff of the timestamps.

var_dump(($ukB->getTimestamp() - $ukA->getTimestamp()) / 3600);

// Output: 49

Huh? So is the difference 48 hours, or not?

echo '$ukA is '.($ukA->format('I') === '1' ? 'IN' : 'NOT IN').' daylight savings'.PHP_EOL;
echo '$ukB is '.($ukB->format('I') === '1' ? 'IN' : 'NOT IN').' daylight savings';

// Output:
$ukA is IN daylight savings
$ukB is NOT IN daylight savings

An extra hour was added due to the transition out of DST at 2 a.m. on October 27th.

[devbysb]

Thanks for the explanations, I understand the problem better. I had already coded a function similar to your suggestion.

To continue thinking, isn't it up to the diff function to return a result based on the time zone and the summer/winter time change? perhaps with additional parameters to know if we want to take daylight saving into account?
I think there are quite a few developers who are faced with these problems and who manage them all with more or less success. I think it's at the language level that it should play out and make life easier for developers. I know that it can take time to finalize, to put in a version, for the OS to recover this version... so for my part I have already coded what I need.