DateInterval::format

(PHP 5 >= 5.3.0, PHP 7)

DateInterval::format — Formats the interval

Description

public string DateInterval::format ( string $format )

Formats the interval.

Parameters

format

**The following characters are recognized in the `format` parameter string. Each format character must be prefixed by a percent sign (%).**
`format` character	Description	Example values
%	Literal %	%
Y	Years, numeric, at least 2 digits with leading 0	01, 03
y	Years, numeric	1, 3
M	Months, numeric, at least 2 digits with leading 0	01, 03, 12
m	Months, numeric	1, 3, 12
D	Days, numeric, at least 2 digits with leading 0	01, 03, 31
d	Days, numeric	1, 3, 31
a	Total number of days as a result of a DateTime::diff() or (unknown) otherwise	4, 18, 8123
H	Hours, numeric, at least 2 digits with leading 0	01, 03, 23
h	Hours, numeric	1, 3, 23
I	Minutes, numeric, at least 2 digits with leading 0	01, 03, 59
i	Minutes, numeric	1, 3, 59
S	Seconds, numeric, at least 2 digits with leading 0	01, 03, 57
s	Seconds, numeric	1, 3, 57
R	Sign "-" when negative, "+" when positive	-, +
r	Sign "-" when negative, empty when positive	-,

Return Values

Returns the formatted interval.

Notes

Note:
The DateInterval::format() method does not recalculate carry over points in time strings nor in date segments. This is expected because it is not possible to overflow values like "32 days" which could be interpreted as anything from "1 month and 4 days" to "1 month and 1 day".

Examples

Example #1 DateInterval example


<?php

$interval = new DateInterval('P2Y4DT6H8M');
echo $interval->format('%d days');

?>

The above example will output:

4 days

Example #2 DateInterval and carry over points


<?php

$interval = new DateInterval('P32D');
echo $interval->format('%d days');

?>

The above example will output:

32 days

Example #3 DateInterval and DateTime::diff() with the %a and %d modifiers


<?php

$january = new DateTime('2010-01-01');
$february = new DateTime('2010-02-01');
$interval = $february->diff($january);

// %a will output the total number of days.
echo $interval->format('%a total days')."\n";

// While %d will only output the number of days not already covered by the
// month.
echo $interval->format('%m month, %d days');

?>

The above example will output:

31 total days
1 month, 0 days

User Contributed Notes

glavic at gmail dot com

2 years ago


How to easy recalculate carry over points:

<?php
class DateIntervalEnhanced extends DateInterval {

    public function recalculate()
    {
        $from = new DateTime;
        $to = clone $from;
        $to = $to->add($this);
        $diff = $from->diff($to);
        foreach ($diff as $k => $v) $this->$k = $v;
        return $this;
    }

}

$di = new DateIntervalEnhanced('PT3600S');
echo "Instead of " . $di->format('%h:%i:%s') . " it outputs " . $di->recalculate()->format('%h:%i:%s');
# output will be: "Instead of 0:0:3600 it outputs 1:0:0"

baptiste dot place at utopiaweb dot fr

6 years ago


With php 5.3, DateTime is sweet !

Here is one quick example :



<?php

/**

 * A sweet interval formatting, will use the two biggest interval parts.

 * On small intervals, you get minutes and seconds.

 * On big intervals, you get months and days.

 * Only the two biggest parts are used. 

 * 

 * @param DateTime $start

 * @param DateTime|null $end

 * @return string

 */

public function formatDateDiff($start, $end=null) {

    if(!($start instanceof DateTime)) {

        $start = new DateTime($start);

    }

    

    if($end === null) {

        $end = new DateTime();

    }

    

    if(!($end instanceof DateTime)) {

        $end = new DateTime($start);

    }

    

    $interval = $end->diff($start);

    $doPlural = function($nb,$str){return $nb>1?$str.'s':$str;}; // adds plurals

    

    $format = array();

    if($interval->y !== 0) {

        $format[] = "%y ".$doPlural($interval->y, "year");

    }

    if($interval->m !== 0) {

        $format[] = "%m ".$doPlural($interval->m, "month");

    }

    if($interval->d !== 0) {

        $format[] = "%d ".$doPlural($interval->d, "day");

    }

    if($interval->h !== 0) {

        $format[] = "%h ".$doPlural($interval->h, "hour");

    }

    if($interval->i !== 0) {

        $format[] = "%i ".$doPlural($interval->i, "minute");

    }

    if($interval->s !== 0) {

        if(!count($format)) {

            return "less than a minute ago";

        } else {

            $format[] = "%s ".$doPlural($interval->s, "second");

        }

    }

    

    // We use the two biggest parts

    if(count($format) > 1) {

        $format = array_shift($format)." and ".array_shift($format);

    } else {

        $format = array_pop($format);

    }

    

    // Prepend 'since ' or whatever you like

    return $interval->format($format);

}

?>

pekka at gmx dot de

5 years ago


Note that `%a` is broken on Windows on VC6 builds. http://bugs.php.net/bug.php?id=51184

balaclark at gmail dot com

4 years ago


Be aware that your default timezone can sometimes alter the result of a diff so that the returned months/days are incorrect. 

There is a bug report at: http://bugs.php.net/bug.php?id=52480

kuzb

5 years ago


Quick class to allow you to input a time in any unit, and have it recalculate in to different denominations (for example, seconds to hours, minutes and seconds):



<?php

    class DateIntervalEnhanced extends DateInterval

    {



      /* Keep in mind that a year is seen in this class as 365 days, and a month is seen as 30 days.         

         It is not possible to calculate how many days are in a given year or month without a point of  

         reference in time.*/

      public function to_seconds()

      {

        return ($this->y * 365 * 24 * 60 * 60) +

               ($this->m * 30 * 24 * 60 * 60) +

               ($this->d * 24 * 60 * 60) +

               ($this->h * 60 * 60) +

               ($this->i * 60) +

               $this->s;

      }

      

      public function recalculate()

      {

        $seconds = $this->to_seconds();

        $this->y = floor($seconds/60/60/24/365);

        $seconds -= $this->y * 31536000;

        $this->m = floor($seconds/60/60/24/30);

        $seconds -= $this->m * 2592000;

        $this->d = floor($seconds/60/60/24);

        $seconds -= $this->d * 86400;

        $this->h = floor($seconds/60/60);

        $seconds -= $this->h * 3600;

        $this->i = floor($seconds/60);

        $seconds -= $this->i * 60;

        $this->s = $seconds;

      }

    }



    // Example usage

    $di = new DateIntervalEnhanced('PT3600S');

    $di->recalculate();

    // outputs 1:0:0 instead of 0:0:3600 now!

    echo $di->format('%H:%i:%s');

?>

beowolve at gmail dot com

2 years ago


German Version of formatDateDiff:

function formatDateDiff($start, $end=null) {
    if(!($start instanceof DateTime)) {
        $start = new DateTime($start);
    }

    if($end === null) {
        $end = new DateTime();
    }

    if(!($end instanceof DateTime)) {
        $end = new DateTime($start);
    }

    $interval = $end->diff($start);
    $doPlural = function($nb,$str){
        if ($nb > 1) {
            switch ($str) {
                case 'Jahr':
                case 'Monat':
                case 'Tag':
                    return $str.'e';
                case 'Stunde':
                case 'Minute':
                case 'Sekunde':
                    return $str.'n';
            }
        } else
            return $str;
    }; // adds plurals

    $format = array();
    if($interval->y !== 0) {
        $format[] = "%y ".$doPlural($interval->y, "Jahr");
    }
    if($interval->m !== 0) {
        $format[] = "%m ".$doPlural($interval->m, "Monat");
    }
    if($interval->d !== 0) {
        $format[] = "%d ".$doPlural($interval->d, "Tag");
    }
    if($interval->h !== 0) {
        $format[] = "%h ".$doPlural($interval->h, "Stunde");
    }
    if($interval->i !== 0) {
        $format[] = "%i ".$doPlural($interval->i, "Minute");
    }
    if($interval->s !== 0) {
        $format[] = "%s ".$doPlural($interval->s, "Sekunde");
    }
    
    if(count($format)==0 || (count($format)==1 && $interval->s !== 0)) {
        return "weniger als eine Minute";
    }

    // We use the two biggest parts
    if(count($format) > 1) {
        $format = array_shift($format).", ".array_shift($format);
    } else {
        $format = array_pop($format);
    }

    // Prepend 'since ' or whatever you like
    return $interval->format($format);
}

zell1285 at gmail dot com

9 days ago


I was doing this: $endDate->diff($startDate)->format('%a’)
to get the number of the days between the end date and the start date. This is correct, but if I subtract 2016-04-23 00:00:00 to 2016-04-02 09:39:01 (note that in only one of the datetime values we have the time) the result is 21 (and not 20 as I expected). This is because the result of the diff is 20 days AND 14 hours, 20 mins and 59 secs. If you use the %a to get the days from a dateinterval, it will round the days (and if the hours are greater than 12, it will round days up). 

So, DO NOT USE the %a formatting to get the difference in days between 2 datetime unless you are 100% sure that both the Datetime objects don't have the time.

You can solve easily with $valueDate->diff($startDate)->days that will return only the days in a dateinterval (without the fuc***g rounding).

me at unreal4u dot com

6 months ago


If you want the difference between two timestamps in HOURS, do not forget to add the number of days: 

<?php
// Bad example
$lastEntryDate = new \DateTime('2015-05-23 00:10:20', new \DateTimeZone('UTC'));
$dateDifference = $lastEntryDate->diff(new \DateTime('2015-05-25 02:35:45', new \DateTimeZone('UTC')));

var_dump((int)$dateDifference->format('%H'));
// Returns 2
if ((int)$dateDifference->format('%H') > 24) {
        // Will never enter here, (int)$dateDifference->format('%H') will contain 0-23 ONLY
}
?>

Instead, sum the days:
<?php
// Bad example
$lastEntryDate = new \DateTime('2015-05-23 00:10:20', new \DateTimeZone('UTC'));
$dateDifference = $lastEntryDate->diff(new \DateTime('2015-05-25 02:35:45', new \DateTimeZone('UTC')));

var_dump(($dateDifference->days * 24 + (int)$dateDifference->format('%H')));
// Returns 50
if (($dateDifference->days * 24 + (int)$dateDifference->format('%H')) > 24) {
        // Will enter here now :)
}
?>

Hope this saves somebody some time and possible bugs :)

kulakov74 at yandex dot ru

2 years ago


glavic, this does not eliminate the problem of "32 days", if you use your class for normalizing intervals of days, because the result will depend on the current month which is used for DateTime by default. And if that does not matter (because the interval is not that long) you don't have to call diff() to get the same recalculation: 
$DT=new DateTime('0000-01-01'); $DT->add($oInt); echo($DT->format('Y-m-d H:i:s'));

DateInterval::format

Description

Parameters

Return Values

Notes

Examples

See Also

User Contributed Notes