(PHP 5 >= 5.5.0, PHP 7, PHP 8)
DateTimeImmutable::setTimestamp — Sets the date and time based on a Unix timestamp
Returns a new DateTimeImmutable object constructed from the old one, with the date and time set based on an Unix timestamp.
timestamp
Unix timestamp representing the date.
Setting timestamps outside the range of int is possible by using
DateTimeImmutable::modify() with the @ format.
Returns a new DateTimeImmutable object with the modified data.
Example #1 DateTimeImmutable::setTimestamp() example
Object-oriented style
<?php
$date = new DateTimeImmutable();
echo $date->format('U = Y-m-d H:i:s') . "\n";
$newDate = $date->setTimestamp(1171502725);
echo $newDate->format('U = Y-m-d H:i:s') . "\n";
?>The above examples will output something similar to:
1272508903 = 2010-04-28 22:41:43 1171502725 = 2007-02-14 20:25:25
This function will not change the value of the DateTimeImmutable object as the method name might suggest. The object, after all, immutable.
<?php
$dti = new DateTimeImmutable();
echo $dti->getTimestamp(); // e.g. 123456789
$dti->setTimestamp(987654321);
echo $dti->getTimestamp(); // 123456789
$x = $dti->setTimestamp (987654321);
echo $x->getTimestamp(); // 987654321
?>While modifying Datetime with the timezone, the user should be aware that changing the timestamp using "@".\time() is not the same as changing the timestamp using setTimestamp().
$now = new \DateTimeImmutable('August 30, 2023 09:00:00 GMT+01');
$origin = $now->getTimestamp(); // 1693382400
$usingAt = $now->modify('@'.$now->getTimestamp())->getTimestamp(); // 1693378800
$usingSetTimestamp = $now->setTimestamp($now->getTimestamp())->getTimestamp(); // 1693382400
var_dump($usingAt === $origin); // false
var_dump($usingSetTimestamp === $origin); // true