How to find the number of hours between two days?

Question

So I have an array of many images in it with their datetimes in the format Y-m-d H:i:s And I wish to find the number of days between the image's date and the current date. This is where I have reached till now...and I'm getting a new error for every small change I make.

$myDateTime = DateTime::createFromFormat('Y-m-d H:i:s', $current_time);
$currentDate = $myDateTime->format('Y-m-d');

foreach($all_images as $key => $am){

        $myDateTime1 = DateTime::createFromFormat('Y-m-d H:i:s', $am['datetime']);
        $imageDate = $myDateTime1->format('Y-m-d');

        $datediff=date_diff($currentDate,$imageDate);
        echo $datediff;
}

I'm getting this error: Warning: date_diff() expects parameter 1 to be DateTimeInterface, string given

Any help would be appreciated! Thanks a lot!

Usually if you deal with date calculations it's easiest to convert both dates into seconds-since-epoch and then just compare them. — neuhaus, Mar 08 '17 at 14:13
Or you could just subtract your two timestamps and divide the result by 3600. — Jerodev, Mar 08 '17 at 14:14
@neuhaus, how can I do that? Like which functions should I use? — meagler, Mar 08 '17 at 14:15
http://stackoverflow.com/questions/3108591/calculate-number-of-hours-between-2-dates-in-php — Yuvaraj Jeganathan, Mar 08 '17 at 14:19
@neuhaus I *think* that is bad advice and I would suggest using the [DateTime object](http://php.net/manual/en/book.datetime.php) rather than the older procedural `mktime` approach. — Martin, Mar 08 '17 at 14:25
Possible duplicate of [Calculate number of hours between 2 dates in PHP](http://stackoverflow.com/questions/3108591/calculate-number-of-hours-between-2-dates-in-php) — Martin, Mar 08 '17 at 14:27

score 2 · Accepted Answer · answered Mar 08 '17 at 14:22

What you've done is you've converted your values to Strings before comparing them, so it's no longer comparing the difference between two dates but instead the difference between two strings. This is your error cause.

Solution:
The values you pass to date_diff need to be two DateTime objects as per the manual:

(PHP 5 >= 5.3.0, PHP 7)
DateTime::diff -- DateTimeImmutable::diff -- DateTimeInterface::diff -- date_diff — Returns the difference between two DateTime objects

Suggestion:

foreach($all_images as $key => $am){

        $myDateTime1 = DateTime::createFromFormat('Y-m-d H:i:s', $am['datetime']);
        $imageDate = $myDateTime1->format('Y-m-d');

        $datediff=date_diff($myDateTime, $myDateTime1);
        echo $datediff->format('%R%a days'); // +2 days
}

Note that the above date_diff function takes Objects not strings.

This will now use date_diff [procedurally in this example] to output a difference value $datediff which you can use with DateTime formatting to reach the number of days/hours/whatever. Please Read the manual.

Good good! I take it if you simply used the object rather than the `->format`ted version that fixed it? — Martin, Mar 08 '17 at 14:34

How to find the number of hours between two days?

1 Answers1