DateTime::format

DateTimeImmutable::format

DateTimeInterface::format

date_format

(PHP 5 >= 5.2.1, PHP 7, PHP 8)

DateTime::format -- DateTimeImmutable::format -- DateTimeInterface::format -- date_format — Returns date formatted according to given format

说明

面向对象风格

public DateTime::format ( string $format ) : string
public DateTimeImmutable::format ( string $format ) : string
public DateTimeInterface::format ( string $format ) : string

过程化风格

date_format ( DateTimeInterface $object , string $format ) : string

Returns date formatted according to given format.

参数

object

仅为过程化风格：由 date_create() 返回的 DateTime 类型的对象。

format

The format of the outputted date string. See the formatting options below. There are also several predefined date constants that may be used instead, so for example DATE_RSS contains the format string 'D, d M Y H:i:s'.

The following characters are recognized in the format parameter string
format character Description Example returned values
Day --- ---
d Day of the month, 2 digits with leading zeros 01 to 31
D A textual representation of a day, three letters Mon through Sun
j Day of the month without leading zeros 1 to 31
l (lowercase 'L') A full textual representation of the day of the week Sunday through Saturday
N ISO-8601 numeric representation of the day of the week 1 (for Monday) through 7 (for Sunday)
S English ordinal suffix for the day of the month, 2 characters st, nd, rd or th. Works well with j
w Numeric representation of the day of the week 0 (for Sunday) through 6 (for Saturday)
z The day of the year (starting from 0) 0 through 365
Week --- ---
W ISO-8601 week number of year, weeks starting on Monday Example: 42 (the 42nd week in the year)
Month --- ---
F A full textual representation of a month, such as January or March January through December
m Numeric representation of a month, with leading zeros 01 through 12
M A short textual representation of a month, three letters Jan through Dec
n Numeric representation of a month, without leading zeros 1 through 12
t Number of days in the given month 28 through 31
Year --- ---
L Whether it's a leap year 1 if it is a leap year, 0 otherwise.
o ISO-8601 week-numbering year. This has the same value as Y, except that if the ISO week number (W) belongs to the previous or next year, that year is used instead. Examples: 1999 or 2003
Y A full numeric representation of a year, 4 digits Examples: 1999 or 2003
y A two digit representation of a year Examples: 99 or 03
Time --- ---
a Lowercase Ante meridiem and Post meridiem am or pm
A Uppercase Ante meridiem and Post meridiem AM or PM
B Swatch Internet time 000 through 999
g 12-hour format of an hour without leading zeros 1 through 12
G 24-hour format of an hour without leading zeros 0 through 23
h 12-hour format of an hour with leading zeros 01 through 12
H 24-hour format of an hour with leading zeros 00 through 23
i Minutes with leading zeros 00 to 59
s Seconds with leading zeros 00 through 59
u Microseconds. Note that date() will always generate 000000 since it takes an int parameter, whereas DateTime::format() does support microseconds if DateTime was created with microseconds. Example: 654321
v Milliseconds. Same note applies as for u. Example: 654
Timezone --- ---
e Timezone identifier Examples: UTC, GMT, Atlantic/Azores
I (capital i) Whether or not the date is in daylight saving time 1 if Daylight Saving Time, 0 otherwise.
O Difference to Greenwich time (GMT) without colon between hours and minutes Example: +0200
P Difference to Greenwich time (GMT) with colon between hours and minutes Example: +02:00
p The same as P, but returns Z instead of +00:00 Example: +02:00
T Timezone abbreviation Examples: EST, MDT ...
Z Timezone offset in seconds. The offset for timezones west of UTC is always negative, and for those east of UTC is always positive. -43200 through 50400
Full Date/Time --- ---
c ISO 8601 date 2004-02-12T15:19:21+00:00
r » RFC 2822 formatted date Example: Thu, 21 Dec 2000 16:01:07 +0200
U Seconds since the Unix Epoch (January 1 1970 00:00:00 GMT) See also time()

Unrecognized characters in the format string will be printed as-is. The Z format will always return 0 when using gmdate().

Note:

Since this function only accepts int timestamps the u format character is only useful when using the date_format() function with user based timestamps created with date_create().

返回值

Returns the formatted date string on success.

更新日志

版本 说明
8.0.0 Prior to this version, false was returned on failure.
8.0.0 The format character p has been added.

范例

Example #1 DateTime::format() example

面向对象风格

<?php
$date = new DateTime('2000-01-01');
echo $date->format('Y-m-d H:i:s');
?>

过程化风格

<?php
$date = date_create('2000-01-01');
echo date_format($date, 'Y-m-d H:i:s');
?>

以上例程会输出：

2000-01-01 00:00:00

注释

This method does not use locales. All output is in English.

参见

  • date() - 格式化一个本地时间／日期

User Contributed Notes

tuxedobob 05-Nov-2020 01:49
I'm actually not sure whether this is a bug, but here's something that tripped me up on PHP 7.3.

I have a date that looks like this: 'November 3, 2020 11:13 (CST)'

I tried to format it using this format string: 'F j, Y H:i (T)'

That didn't work.

What *did* work was the format string without the parentheses: 'F j, Y H:i T'.

This string also parsed the timezone when the time zone *didn't* have parentheses surrounding it: 'November 3, 2020 11:13 CST'.

It seems as though the T token is a little greedy with surrounding parentheses, so don't include them in your format string.
sparcbr at gmail dot com 27-Sep-2020 06:24
To add literal characteres youi can escape with backslash (\):

$date = new DateTime();
echo $date->format('Ymd\Thms');
info at ibusweb dot com 09-Mar-2019 10:12
$saved_time="2019-03-09 14:25:20";
    $formated_saved_time = new DateTime($saved_time);
    $current_time = new DateTime();
    $interval = $current_time->diff($formated_saved_time);
 
      if (!empty($interval->format('%a'))){
       $time_difference=$interval->format('%a days ago');
        } elseif ($formated_saved_time->format('d') != $current_time->format('d')){
             $time_difference="yesterday";
             }elseif (!empty($interval->format('%h'))){
                     $time_difference=$interval->format('%h hr, %i min ago');
                     } elseif (!empty($interval->format('%i'))){
                              $time_difference=$interval->format('%i min ago');
                              } elseif (!empty($interval->format('%s'))){
                                $time_difference=$interval->format('%s sec ago');
  }

output ----- posted 4 hr, 12 min ago at 2019-03-09 14:25:20

see the code in action here
https://eval.in/1081921
mesa dot fx at gmail dot com 17-Dec-2018 01:21
There is a bit confusing logic may appear using year week number:

<?php
echo (new \DateTime("2018-12-31 13:05:21"))->format("YW") . PHP_EOL;
?>

will output 201801, not 201901 nor 201852, because of strange ISO_8601-2004 standard: the  first  calendar  week  of  a  year  is  that  one  which  includes  the  first  Thursday  of  that  year, so this date (it is Monday) do belong to the first week of 2019 (this is why 'W' format gives 01), but internal timestamp is of 2018 (and 'Y' format obey this), therefore getting us unexpected result of 201801. So be careful when using this output with something important (i know projects where this was used to form MySQL partitions).
prussell at cloudworksconsulting dot com 15-Sep-2014 12:02
The udate function is a great start, but the formatting of the milliseconds is a little off. If it is within the first 100000 microseconds then the string will be less than 6 characters, so 0.012435 will appear as 0.12345. The revision below fixes this.

function udate($strFormat = 'u', $uTimeStamp = null)
{

    // If the time wasn't provided then fill it in
    if (is_null($uTimeStamp))
    {
        $uTimeStamp = microtime(true);
    }

    // Round the time down to the second
    $dtTimeStamp = floor($uTimeStamp);

    // Determine the millisecond value
    $intMilliseconds = round(($uTimeStamp - $dtTimeStamp) * 1000000);
    // Format the milliseconds as a 6 character string
    $strMilliseconds = str_pad($intMilliseconds, 6, '0', STR_PAD_LEFT);

    // Replace the milliseconds in the date format string
    // Then use the date function to process the rest of the string
    return date(preg_replace('`(?<!\\\\)u`', $strMilliseconds, $strFormat), $dtTimeStamp);
}
soul dot enforcer at gmail dot com 02-Apr-2014 12:48
For full reference of the supported format character and results,
see the documentation of date() :
http://www.php.net/manual/en/function.date.php
chris at codewiz dot biz 13-Feb-2014 02:47
I believe this is a bug but its note-worthy if it is intended (I am using PHP 5.5.3).

$ php --version

PHP Warning:  Module 'xdebug' already loaded in Unknown on line 0
PHP 5.5.3-1ubuntu2.1 (cli) (built: Dec 12 2013 04:24:35)
Copyright (c) 1997-2013 The PHP Group
Zend Engine v2.5.0, Copyright (c) 1998-2013 Zend Technologies
    with Xdebug v2.2.3, Copyright (c) 2002-2013, by Derick Rethans
    with Zend OPcache v7.0.3-dev, Copyright (c) 1999-2013, by Zend Technologies

What is happening:

DateTime()->format() will modify the timezone. So do not expect the public date property to be returned (format mask applied) based on the current public timezone property. format will decide that when calling ->format() it will use the server timezone which eliminates all usefulness of ->setTimezone().

<?php
            $nowUtc = new \DateTime( 'now',  new \DateTimeZone( 'UTC' ) );
            echo '$nowUtc'.PHP_EOL;
            var_dump($nowUtc);
            $nowUtc = new \DateTime( 'now',  new \DateTimeZone( 'UTC' ) );
            echo '$nowUtc->format(\'Y-m-d h:i:s\')'.PHP_EOL;
            var_dump($nowUtc->format('Y-m-d h:i:s'));
            $nowUtc->setTimezone( new \DateTimeZone( 'Australia/Sydney' ) );
            echo '$nowUtc->setTimezone( new \DateTimeZone( \'Australia/Sydney\' ) )'.PHP_EOL;
            var_dump($nowUtc);
            echo '$nowUtc->format(\'Y-m-d h:i:s\')'.PHP_EOL;
            var_dump($nowUtc->format('Y-m-d h:i:s'));exit;
?>

outputs;

$nowUtc

object(DateTime)[2607]
  public 'date' => string '2014-02-13 02:42:48' (length=19)
  public 'timezone_type' => int 3
  public 'timezone' => string 'UTC' (length=3)

$nowUtc->format('Y-m-d h:i:s')

string '2014-02-13 02:42:48' (length=19)

$nowUtc->setTimezone( new \DateTimeZone( 'Australia/Sydney' ) )

object(DateTime)[2608]
  public 'date' => string '2014-02-13 13:42:48' (length=19)
  public 'timezone_type' => int 3
  public 'timezone' => string 'Australia/Sydney' (length=16)

$nowUtc->format('Y-m-d h:i:s')

string '2014-02-13 01:42:48' (length=19) // expected 2014-02-13 13:42:48 based on Australia/Sydney - what is 2014-02-13 01:42:48 from anyway!
daysnine at gmail dot com 04-Nov-2013 11:02
Seems like datetime::format does not really support microseconds as the documentation under date suggest it will.

Here is some code to generate a datetime with microseconds and timezone:

private function udate($format = 'u', $utimestamp = null) {
        if (is_null($utimestamp))
            $utimestamp = microtime(true);

        $timestamp = floor($utimestamp);
        $milliseconds = round(($utimestamp - $timestamp) * 1000000);

        return date(preg_replace('`(?<!\\\\)u`', $milliseconds, $format), $timestamp);
    }

echo udate('Y-m-d H:i:s.u T');
// Will output something like: 2014-01-01 12:20:24.42342 CET
craig dot constable at gmail dot com 02-Mar-2012 04:24
Using a datetime field from a mysql database e.g. "2012-03-24 17:45:12"

<?php

$result = mysql_query("SELECT `datetime` FROM `table`");
$row = mysql_fetch_row($result);
$date = date_create($row[0]);

echo date_format($date, 'Y-m-d H:i:s');
#output: 2012-03-24 17:45:12

echo date_format($date, 'd/m/Y H:i:s');
#output: 24/03/2012 17:45:12

echo date_format($date, 'd/m/y');
#output: 24/03/12

echo date_format($date, 'g:i A');
#output: 5:45 PM

echo date_format($date, 'G:ia');
#output: 05:45pm

echo date_format($date, 'g:ia \o\n l jS F Y');
#output: 5:45pm on Saturday 24th March 2012

?>
ca at agercon dot dk 01-Jul-2011 08:16
The date_format can be use to get the last day of February:

<?php

function last_day_of_feb ($year) {
# The 0th day of a month is the same as the last day of the month before
        $ultimo_feb_str = $year . "-03-00";
        $ultimo_feb_date = date_create($ultimo_feb_str);
        $return = date_format($ultimo_feb_date, "Y-m-d");
        return $return;
}

echo last_day_of_feb(2011) . "\n"; # 2011-02-28
echo last_day_of_feb(2012) . "\n"; # 2011-02-29

?>