DateTimeImmutable::add

(PHP 5 >= 5.5.0, PHP 7, PHP 8)

DateTimeImmutable::add — Returns a new object, with added amount of days, months, years, hours, minutes and seconds

Description

public DateTimeImmutable::add(DateInterval $interval): DateTimeImmutable

Creates a new DateTimeImmutable object, and adds the specified DateInterval object to this, to represent the new value.

Parameters

interval

A DateInterval object

Return Values

Returns a new DateTimeImmutable object with the modified data.

Examples

Example #1 DateTimeImmutable::add() example

Object-oriented style

<?php
$date = new DateTimeImmutable('2000-01-01');
$newDate = $date->add(new DateInterval('P10D'));
echo $newDate->format('Y-m-d') . "\n";
?>

Example #2 Further DateTimeImmutable::add() examples

<?php
$date = new DateTimeImmutable('2000-01-01');
$newDate = $date->add(new DateInterval('PT10H30S'));
echo $newDate->format('Y-m-d H:i:s') . "\n";

$date = new DateTimeImmutable('2000-01-01');
$newDate = $date->add(new DateInterval('P7Y5M4DT4H3M2S'));
echo $newDate->format('Y-m-d H:i:s') . "\n";
?>

The above example will output:

2000-01-01 10:00:30
2007-06-05 04:03:02

Example #3 Beware when adding months

<?php
$date = new DateTimeImmutable('2000-12-31');
$interval = new DateInterval('P1M');

$newDate1 = $date->add($interval);
echo $newDate1->format('Y-m-d') . "\n";

$newDate2 = $newDate1->add($interval);
echo $newDate2->format('Y-m-d') . "\n";
?>

The above example will output:

2001-01-31
2001-03-03

See Also