Last updated: Fri, 30 Oct 2009

DateTime::modify

(PHP 5 >= 5.2.0)

DateTime::modify — Alters the timestamp

Beschreibung

public DateTime DateTime::modify ( string $modify )

DateTime date_modify ( DateTime $object , string $modify )

Alter the timestamp of a DateTime object by incrementing or decrementing in a format accepted by strtotime().

Parameter-Liste

object: Nur bei prozeduralem Aufruf: Ein von date_create() zurückgegebens DateTime Objekt.
modify: String in a relative format accepted by strtotime().

Rückgabewerte

Returns the modified DateTime.

Changelog

Version	Beschreibung
5.3.0	Der Rückgabewert wurde von `NULL` auf DateTime geändert.

Beispiele

Beispiel #1 A date_modify() example


<?php
$date = new DateTime("2006-12-12");
$date->modify("+1 day");
echo $date->format("Y-m-d");
?>

Das oben gezeigte Beispiel erzeugt folgende Ausgabe:

2006-12-13

Siehe auch

strtotime() - Wandelt ein beliebiges in englischer Textform angegebenes Datum in einen UNIX-Zeitstempel (Timestamp) um

DateTime::__set_state

DateTime::getTimezone

Last updated: Fri, 30 Oct 2009

add a note User Contributed Notes
DateTime::modify

tacker at php dot net
03-Jul-2009 10:18


Do not use '[+/-]{n} month' to get the last day of the month.





If you use '+1 month' on the first of the month, it sets the date to the next first of the month.  This behaviour gives the impression, that php considers the length of a month, which is not true.





Basically if you use '+1 month' it takes the month number, adds 1 and parses result as a new date.  But if you use '+1 month' on the last day of a month, the result is unexpected as 2009-05-31 becomes 2009-06-31 which is an invalid date and then interpreted as 2009-07-01.

tom at r dot je
18-Jun-2009 02:43


If you want to find the next working day (assuming mon-fri) you can use this:



<?php

$d = new DateTime();



$day = $d->format('w');



if ($day == 0 || $day >= 5) $d->modify('+' . ((7-$day+1) % 7) . ' days');

else $d->modify('+1 day');

?>

Cas Adriani
15-Jun-2009 10:51


I couldn't find a function to skip to the begin of a week or end of a week so I found an easy way to do so. Hopefully it's helpful to others.



<?php

$d = new DateTime();



//Set object to begin (Monday) of the week

$d->modify( "-" . ( $d->format("N") - 1 ) . ' days' );

echo $d->format("m-d");



//Set object to end (Sunday) of the week

$d->modify( "+" . ( 7 - $d->format("N") ) . ' days' );

echo $d->format("m-d");

?>

Anodyne
31-Mar-2009 04:04


As far as I can tell, the documentation for date_modify seems to be inconsistent with the functionality exhibited in PHP 5.2.9 (and perhaps other versions)



I was trying to figure out why a call to date_modify was returning null in PHP 5.2.9. An older version of the documentation for date_modify at http://php.chinaunix.net/manual/zh/function.date-modify.php (for PHP 5 >= 5.1.0) explains that date_modify returns NULL on success, or FALSE on failure. 



I suspect the new version of date_modify returns a DateTime object instead of null or false:



PRESUMABLY NEW:

DateTime date_modify  ( DateTime $object  , string $modify  )



OLD:

null/boolean date_modify  ( DateTime $object  , string $modify  )

add a note

DateTime::__set_state

DateTime::getTimezone

Last updated: Fri, 30 Oct 2009