downloads | documentation | faq | getting help | mailing lists | licenses | wiki | reporting bugs | php.net sites | conferences | my php.net

search for in the

DateTime::add> <Predefined Constants
[edit] Last updated: Fri, 26 Apr 2013

view this page in

The DateTime class

(PHP 5 >= 5.2.0)

Introduction

Representation of date and time.

Class synopsis

DateTime {
/* Constants */
const string ATOM = "Y-m-d\TH:i:sP" ;
const string COOKIE = "l, d-M-y H:i:s T" ;
const string ISO8601 = "Y-m-d\TH:i:sO" ;
const string RFC822 = "D, d M y H:i:s O" ;
const string RFC850 = "l, d-M-y H:i:s T" ;
const string RFC1036 = "D, d M y H:i:s O" ;
const string RFC1123 = "D, d M Y H:i:s O" ;
const string RFC2822 = "D, d M Y H:i:s O" ;
const string RFC3339 = "Y-m-d\TH:i:sP" ;
const string RSS = "D, d M Y H:i:s O" ;
const string W3C = "Y-m-d\TH:i:sP" ;
/* Methods */
public __construct ([ string $time = "now" [, DateTimeZone $timezone = NULL ]] )
public DateTime add ( DateInterval $interval )
public static DateTime createFromFormat ( string $format , string $time [, DateTimeZone $timezone ] )
public DateInterval diff ( DateTime $datetime2 [, bool $absolute = false ] )
public string format ( string $format )
public static array getLastErrors ( void )
public int getOffset ( void )
public int getTimestamp ( void )
public DateTimeZone getTimezone ( void )
public DateTime modify ( string $modify )
public static DateTime __set_state ( array $array )
public DateTime setDate ( int $year , int $month , int $day )
public DateTime setISODate ( int $year , int $week [, int $day = 1 ] )
public DateTime setTime ( int $hour , int $minute [, int $second = 0 ] )
public DateTime setTimestamp ( int $unixtimestamp )
public DateTime setTimezone ( DateTimeZone $timezone )
public DateTime sub ( DateInterval $interval )
public DateTime __wakeup ( void )
}

Predefined Constants

DateTime::ATOM
DATE_ATOM
Atom (example: 2005-08-15T15:52:01+00:00)
DateTime::COOKIE
DATE_COOKIE
HTTP Cookies (example: Monday, 15-Aug-05 15:52:01 UTC)
DateTime::ISO8601
DATE_ISO8601
ISO-8601 (example: 2005-08-15T15:52:01+0000)
DateTime::RFC822
DATE_RFC822
RFC 822 (example: Mon, 15 Aug 05 15:52:01 +0000)
DateTime::RFC850
DATE_RFC850
RFC 850 (example: Monday, 15-Aug-05 15:52:01 UTC)
DateTime::RFC1036
DATE_RFC1036
RFC 1036 (example: Mon, 15 Aug 05 15:52:01 +0000)
DateTime::RFC1123
DATE_RFC1123
RFC 1123 (example: Mon, 15 Aug 2005 15:52:01 +0000)
DateTime::RFC2822
DATE_RFC2822
RFC 2822 (Mon, 15 Aug 2005 15:52:01 +0000)
DateTime::RFC3339
DATE_RFC3339
Same as DATE_ATOM (since PHP 5.1.3)
DateTime::RSS
DATE_RSS
RSS (Mon, 15 Aug 2005 15:52:01 +0000)
DateTime::W3C
DATE_W3C
World Wide Web Consortium (example: 2005-08-15T15:52:01+00:00)

Changelog

Version Description
5.2.2 DateTime object comparison with the comparison operators changed to work as expected. Previously, all DateTime objects were considered equal (using ==).

Table of Contents



DateTime::add> <Predefined Constants
[edit] Last updated: Fri, 26 Apr 2013
 
add a note add a note User Contributed Notes DateTime - [11 notes]
up
6
ediathome
3 years ago
If you need DateTime::createFromFormat functionality in versions <5.3.0 releases you might use the following basic class which can also be combined with Tom's class. It should work for most basic formats, however you should improve this function if you need more complex formats.

<?php
class DateClass extends DateTime{

public function getTimestamp(){
    return $this->format ("U");
}

/**
*    This function calculates the number of days between the first and the second date. Arguments must be subclasses of DateTime
**/
static function differenceInDays ($firstDate, $secondDate){
    $firstDateTimeStamp = $firstDate->format("U");
    $secondDateTimeStamp = $secondDate->format("U");
    $rv = round ((($firstDateTimeStamp - $secondDateTimeStamp))/86400);
    return $rv;
}

/**
* This function returns an object of DateClass from $time in format $format. See date() for possible values for $format
**/
static function createFromFormat ($format, $time){
    assert ($format!="");
    if($time==""){
        return new DateClass();
    }

    $regexpArray['Y'] = "(?P<Y>19|20\d\d)";       
    $regexpArray['m'] = "(?P<m>0[1-9]|1[012])";
    $regexpArray['d'] = "(?P<d>0[1-9]|[12][0-9]|3[01])";
    $regexpArray['-'] = "[-]";
    $regexpArray['.'] = "[\. /.]";
    $regexpArray[':'] = "[:]";           
    $regexpArray['space'] = "[\s]";
    $regexpArray['H'] = "(?P<H>0[0-9]|1[0-9]|2[0-3])";
    $regexpArray['i'] = "(?P<i>[0-5][0-9])";
    $regexpArray['s'] = "(?P<s>[0-5][0-9])";

    $formatArray = str_split ($format);
    $regex = "";

    // create the regular expression
    foreach($formatArray as $character){
        if ($character==" ") $regex = $regex.$regexpArray['space'];
        elseif (array_key_exists($character, $regexpArray)) $regex = $regex.$regexpArray[$character];
    }
    $regex = "/".$regex."/";

    // get results for regualar expression
    preg_match ($regex, $time, $result);

    // create the init string for the new DateTime
    $initString = $result['Y']."-".$result['m']."-".$result['d'];

// if no value for hours, minutes and seconds was found add 00:00:00
    if (isset($result['H'])) $initString = $initString." ".$result['H'].":".$result['i'].":".$result['s'];
    else {$initString = $initString." 00:00:00";}

    $newDate = new DateClass ($initString);
    return $newDate;
    }   
}

?>
up
2
tim at timfennis dot com
2 months ago
There is a subtle difference between the following two statments which causes JavaScript's Date object on iPhones to fail.

<?php
$objDateTime = new DateTime('NOW');
echo $objDateTime->format('c'); // ISO8601 formated datetime
echo $objDateTime->format(DateTime::ISO8601); // Another way to get an ISO8601 formatted string

/**
On my local machine this results in:

2013-03-01T16:15:09+01:00
2013-03-01T16:15:09+0100

Both of these strings are valid ISO8601 datetime strings, but the latter is not accepted by the constructor of JavaScript's date object on iPhone. (Possibly other browsers as well)
*/

?>

Our solution was to create the following constant on our DateHelper object.

<?php
class DateHelper
{
    /**
     * An ISO8601 format string for PHP's date functions that's compatible with JavaScript's Date's constructor method
     * Example: 2013-04-12T16:40:00-04:00
     *
     * PHP's ISO8601 constant doesn't add the colon to the timezone offset which is required for iPhone
    **/
    const ISO8601 = 'Y-m-d\TH:i:sP';
}
?>
up
4
php at keith tyler dot com
10 months ago
DateTime does not support split seconds (microseconds or milliseconds etc.)
I don't know why this isn't documented.
The class constructor will accept them without complaint, but they are discarded.
There does not appear to be a way to take a string like "2012-07-08 11:14:15.638276" and store it in an objective form in a complete way.

So you cannot do date math on two strings such as:

<?php
$d1=new DateTime("2012-07-08 11:14:15.638276");
$d2=new DateTime("2012-07-08 11:14:15.889342");
$diff=$d2->diff($d1);
print_r( $diff ) ;

/* returns:

DateInterval Object
(
    [y] => 0
    [m] => 0
    [d] => 0
    [h] => 0
    [i] => 0
    [s] => 0
    [invert] => 0
    [days] => 0
)

*/
?>

You get back 0 when you actually want to get 0.251066 seconds.
up
1
bf at tbwb dot nl
2 years ago
If you have timezone information in the time string you construct the DateTime object with, you cannot add an extra timezone in the constructor. It will ignore the timezone information in the time string:

$date = new DateTime("2010-07-05T06:00:00Z", new DateTimeZone("Europe/Amsterdam"));

will create a DateTime object set to "2010-07-05 06:00:00+0200" (+2 being the TZ offset for Europe/Amsterdam)

To get this done, you will need to set the timezone separately:

$date = new DateTime("2010-07-05T06:00:00Z");
$date->setTimeZone(new DateTimeZone("Europe/Amsterdam");

This will create a DateTime object set to "2010-07-05 08:00:00+0200"
up
0
marcio dot barbado at bdslabs dot com dot br
1 year ago
DateTime class does not use locales so here I test and compare its formating with strftime() function's one:

    <?php
      // Under UNIX, command "$ locale -a" should provide you with your server's options.

      $data_do_mysql            = "2011-09-29 23:50:26";

      echo '<strong>' . "\$data_do_mysql" . '</strong>' . ":" . $data_do_mysql . "." . '<br />' .
           '<br />';

      $dataInicial            = new DateTime(trim($data_do_mysql));

      // setlocale() used with strftime().
      $meu_locale            = setlocale(LC_ALL, "pt_BR.utf8");
      $data_inicial            = strftime("%d de %b de %Y", strtotime(trim($data_do_mysql)));

      // Outputs:
      // $data_do_mysql formatada com a classe DateTime:29-Sep-2011.
      echo '<strong>' . "\$data_do_mysql" . '</strong>' . " formatada com a classe DateTime:" . $dataInicial->format('d-M-Y') . "." . '<br />' .
           '<br />';

      // Outputs:
      // $data_do_mysql formatada com a função strftime():29 de Set de 2011.
      echo '<strong>' . "\$data_do_mysql" . '</strong>' . " formatada com a fun&ccedil;&atilde;o strftime():" . $data_inicial . "." . '<br />' .
           '<br />';

      // setlocale() fails :-(
      if (!$meu_locale)
        {
            echo "Prefiro usar DateTime.";
        }

      // Yay setlocale() :-D
      else
        {
            echo "Prefiro usar strftime().";
        }

      exit();
    ?>
up
0
petepostma@google
2 months ago
const string RFC822 = "D, d M y H:i:s O" ;
would be incorrect; 822 != 2822.

822 defines the timezone to be a limited set of characters, preferably 'GMT', not digits like 2822.

const string RFC822 = "D, d M y H:i:s T" ;
up
0
gmblar+php at gmail dot com
3 years ago
Small but powerful extension to DateTime

<?php

class Blar_DateTime extends DateTime {

    /**
     * Return Date in ISO8601 format
     *
     * @return String
     */
    public function __toString() {
        return $this->format('Y-m-d H:i');
    }

    /**
     * Return difference between $this and $now
     *
     * @param Datetime|String $now
     * @return DateInterval
     */
    public function diff($now = 'NOW') {
        if(!($now instanceOf DateTime)) {
            $now = new DateTime($now);
        }
        return parent::diff($now);
    }

    /**
     * Return Age in Years
     *
     * @param Datetime|String $now
     * @return Integer
     */
    public function getAge($now = 'NOW') {
        return $this->diff($now)->format('%y');
    }

}

?>

Usage:

<?php

$birthday = new Blar_DateTime('1879-03-14');

// Example 1
echo $birthday;
// Result: 1879-03-14 00:00

// Example 2
echo '<p>Albert Einstein would now be ', $birthday->getAge(), ' years old.</p>';
// Result: <p>Albert Einstein would now be 130 years old.</p>

// Example 3
echo '<p>Albert Einstein would now be ', $birthday->diff()->format('%y Years, %m Months, %d Days'), ' old.</p>';
// Result: <p>Albert Einstein would now be 130 Years, 10 Months, 10 Days old.</p>

// Example 4
echo '<p>Albert Einstein was on 2010-10-10 ', $birthday->getAge('2010-10-10'), ' years old.</p>';
// Result: <p>Albert Einstein was on 2010-10-10 131 years old.</p>

?>
up
-1
nodweber at gmail dot com
1 year ago
IF You want to create clone of $time, use clone..

<?php
  $now   = new DateTime;
  $clone = $now;        //this doesnot clone so:
  $clone->modify( '-1 day' );
 
  echo $now->format( 'd-m-Y' ), "\n", $clone->format( 'd-m-Y' );
  echo '----', "\n";

  // will print same.. if you want to clone make like this:
  $now   = new DateTime;
  $clone = clone $now;   
  $clone->modify( '-1 day' );
   
  echo $now->format( 'd-m-Y' ), "\n", $clone->format( 'd-m-Y' );
?>

Results:
18-07-2011
18-07-2011
----
19-07-2011
18-07-2011
up
-1
giorgio dot liscio at email dot it
2 years ago
please note that using

setTimezone
setTimestamp
setDate
setTime
etc..

will modify the original object, and the return value is $this

$original = new DateTime("now");

$modified = $original->setTimezone(new DateTimezone("europe/rome"));

echo $original === $modified ? "THE OBJECT IS THE SAME" : "OBJECTS ARE DIFFERENT";

so a datetime object is mutable
up
-1
tom at r dot je
3 years ago
If you're stuck on a PHP 5.1 system (unfortunately one of my clients is on a rather horrible webhost who claims they cannot upgrade php) you can use this as a quick workaround:

<?php
if (!class_exists('DateTime')) {
class DateTime {
    public $date;
   
    public function __construct($date) {
        $this->date = strtotime($date);
    }
   
    public function setTimeZone($timezone) {
        return;
    }
   
    private function __getDate() {
        return date(DATE_ATOM, $this->date);   
    }
   
    public function modify($multiplier) {
        $this->date = strtotime($this->__getDate() . ' ' . $multiplier);
    }
   
    public function format($format) {
        return date($format, $this->date);
    }
}
}
?>

it is NOT perfect. Timezones and DST are not supported, but if you just need compatible basic functions this works. Feel free to complete this so it's compatible with the 5.2 datetime object.
up
-2
Julien
9 months ago
DateTime extension that work with millisecond

<?php
class MilliSecondDateTime extends Datetime{

    private $millisecond;

    public function __construct($time = NULL,$time_zone = NULL){
       
        if(is_null($time))
            $time = '@'.microtime(true);

        if(is_null($time_zone))
            $time_zone = new DateTimeZone('UTC');

        if(preg_match('/@(\\\\d+)\\\\.(\\\\d+)/',$time,$matches)){
            $this->millisecond = $matches[2];
            parent::__construct('@'.$matches[1],$time_zone);
        } else {
            $this->millisecond = 0;
            parent::__construct($time,$time_zone);
        }
    }

    public function getSQLDate(){
        return $this->format('Y-m-d G:i:s').'.'.$this->millisecond;
    }

}
?>

Note that sub() method continue to work with millisecond
add a note add a note

 
show source | credits | stats | sitemap | contact | advertising | mirror sites