The DateInterval class
(PHP 5 >= 5.3.0)
Introduction
Represents a date interval.
A date interval stores either a fixed amount of time (in years, months, days, hours etc) or a relative time string in the format that DateTime's constructor supports.
Class synopsis
Properties
- y
-
Number of years.
- m
-
Number of months.
- d
-
Number of days.
- h
-
Number of hours.
- i
-
Number of minutes.
- s
-
Number of seconds.
- invert
-
Is 1 if the interval represents a negative time period and 0 otherwise. See DateInterval::format().
- days
-
If the DateInterval object was created by DateTime::diff(), then this is the total number of days between the start and end dates. Otherwise, days will be
FALSE.Before PHP 5.4.20/5.5.4 instead of
FALSEyou will receive -99999 upon accessing the property.
Table of Contents
- DateInterval::__construct — Creates a new DateInterval object
- DateInterval::createFromDateString — Sets up a DateInterval from the relative parts of the string
- DateInterval::format — Formats the interval
Коментарии
If you want to reverse a date interval use array_reverse and iterator_to_array. I've found using invert to be unreliable.
<?php
$start_date = date_create("2021-01-01");
$end_date = date_create("2021-01-05"); // If you want to include this date, add 1 day
$interval = DateInterval::createFromDateString('1 day');
$daterange = new DatePeriod($start_date, $interval ,$end_date);
function show_dates ($dr) {
foreach($dr as $date1){
echo $date1->format('Y-m-d').'<br>';
}
}
show_dates ($daterange);
echo '<br>';
// reverse the array
$daterange = array_reverse(iterator_to_array($daterange));
show_dates ($daterange);
?>
Gives
2021-01-01
2021-01-02
2021-01-03
2021-01-04
2021-01-04
2021-01-03
2021-01-02
2021-01-01
More simple example i use to add or subtract.
<?php
$Datetime = new Datetime('NOW', new DateTimeZone('America/Bahia'));
$Datetime->add(DateInterval::createFromDateString('2 day'));
echo $Datetime->format("Y-m-d H:i:s");
?>
There is a handy way to compare intervals by adding them to 0 dates and comparing dates instead
<?php
function compare(DateInterval $first, DateInterval $second): int
{
$firstDate = (new DateTime())->setTimestamp(0)->add($first);
$secondDate = (new DateTime())->setTimestamp(0)->add($second);
return $firstDate <=> $secondDate;
}
echo compare(new DateInterval('P2D'), new DateInterval('PT48H')) . PHP_EOL;
echo compare(DateInterval::createFromDateString('2 days'), DateInterval::createFromDateString('48 hours')) . PHP_EOL;
echo compare(DateInterval::createFromDateString('2 days'), DateInterval::createFromDateString('49 hours')) . PHP_EOL;
echo compare(DateInterval::createFromDateString('2 days'), DateInterval::createFromDateString('47 hours')) . PHP_EOL;
?>
Outputs:
0
0
-1
1