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DateTime::createFromFormat

date_create_from_format

(PHP 5 >= 5.3.0, PHP 7)

DateTime::createFromFormat -- date_create_from_formatReturns new DateTime object formatted according to the specified format

说明

面向对象风格

public static DateTime DateTime::createFromFormat ( string $format , string $time [, DateTimeZone $timezone ] )

过程化风格

DateTime date_create_from_format ( string $format , string $time [, DateTimeZone $timezone ] )

Returns new DateTime object formatted according to the specified format.

参数

format

The format that the passed in string should be in. See the formatting options below. In most cases, the same letters as for the date() can be used.

The following characters are recognized in the format parameter string
format character Description Example parsable values
Day --- ---
d and j Day of the month, 2 digits with or without leading zeros 01 to 31 or 1 to 31
D and l A textual representation of a day Mon through Sun or Sunday through Saturday
S English ordinal suffix for the day of the month, 2 characters. It's ignored while processing. st, nd, rd or th.
z The day of the year (starting from 0) 0 through 365
Month --- ---
F and M A textual representation of a month, such as January or Sept January through December or Jan through Dec
m and n Numeric representation of a month, with or without leading zeros 01 through 12 or 1 through 12
Year --- ---
Y A full numeric representation of a year, 4 digits Examples: 1999 or 2003
y A two digit representation of a year (which is assumed to be in the range 1970-2069, inclusive) Examples: 99 or 03 (which will be interpreted as 1999 and 2003, respectively)
Time --- ---
a and A Ante meridiem and Post meridiem am or pm
g and h 12-hour format of an hour with or without leading zero 1 through 12 or 01 through 12
G and H 24-hour format of an hour with or without leading zeros 0 through 23 or 00 through 23
i Minutes with leading zeros 00 to 59
s Seconds, with leading zeros 00 through 59
u Microseconds (up to six digits) Example: 45, 654321
Timezone --- ---
e, O, P and T Timezone identifier, or difference to UTC in hours, or difference to UTC with colon between hours and minutes, or timezone abbreviation Examples: UTC, GMT, Atlantic/Azores or +0200 or +02:00 or EST, MDT
Full Date/Time --- ---
U Seconds since the Unix Epoch (January 1 1970 00:00:00 GMT) Example: 1292177455
Whitespace and Separators --- ---
(space) One space or one tab Example:
# One of the following separation symbol: ;, :, /, ., ,, -, ( or ) Example: /
;, :, /, ., ,, -, ( or ) The specified character. Example: -
? A random byte Example: ^ (Be aware that for UTF-8 characters you might need more than one ?. In this case, using * is probably what you want instead)
* Random bytes until the next separator or digit Example: * in Y-*-d with the string 2009-aWord-08 will match aWord
! Resets all fields (year, month, day, hour, minute, second, fraction and timzone information) to the Unix Epoch Without !, all fields will be set to the current date and time.
| Resets all fields (year, month, day, hour, minute, second, fraction and timzone information) to the Unix Epoch if they have not been parsed yet Y-m-d| will set the year, month and day to the information found in the string to parse, and sets the hour, minute and second to 0.
+ If this format specifier is present, trailing data in the string will not cause an error, but a warning instead Use DateTime::getLastErrors() to find out whether trailing data was present.

Unrecognized characters in the format string will cause the parsing to fail and an error message is appended to the returned structure. You can query error messages with DateTime::getLastErrors() .

If format does not contain the character ! then portions of the generated time which are not specified in format will be set to the current system time.

If format contains the character !, then portions of the generated time not provided in format, as well as values to the left-hand side of the !, will be set to corresponding values from the Unix epoch.

The Unix epoch is 1970-01-01 00:00:00 UTC.

time

String representing the time.

timezone

A DateTimeZone object representing the desired time zone.

If timezone is omitted and time contains no timezone, the current timezone will be used.

Note:

The timezone parameter and the current timezone are ignored when the time parameter either contains a UNIX timestamp (e.g. 946684800) or specifies a timezone (e.g. 2010-01-28T15:00:00+02:00).

返回值

Returns a new DateTime instance 或者在失败时返回 FALSE .

更新日志

版本 说明
5.3.9 The + format specifier has been added.

范例

Example #1 DateTime::createFromFormat() example

面向对象风格

<?php
$date 
DateTime :: createFromFormat ( 'j-M-Y' '15-Feb-2009' );
echo 
$date -> format ( 'Y-m-d' );
?>

过程化风格

<?php
$date 
date_create_from_format ( 'j-M-Y' '15-Feb-2009' );
echo 
date_format ( $date 'Y-m-d' );
?>

以上例程会输出:

2009-02-15

Example #2 Intricacies of DateTime::createFromFormat()

<?php
echo  'Current time: '  date ( 'Y-m-d H:i:s' ) .  "\n" ;

$format  'Y-m-d' ;
$date  DateTime :: createFromFormat ( $format '2009-02-15' );
echo 
"Format:  $format ; "  $date -> format ( 'Y-m-d H:i:s' ) .  "\n" ;

$format  'Y-m-d H:i:s' ;
$date  DateTime :: createFromFormat ( $format '2009-02-15 15:16:17' );
echo 
"Format:  $format ; "  $date -> format ( 'Y-m-d H:i:s' ) .  "\n" ;

$format  'Y-m-!d H:i:s' ;
$date  DateTime :: createFromFormat ( $format '2009-02-15 15:16:17' );
echo 
"Format:  $format ; "  $date -> format ( 'Y-m-d H:i:s' ) .  "\n" ;

$format  '!d' ;
$date  DateTime :: createFromFormat ( $format '15' );
echo 
"Format:  $format ; "  $date -> format ( 'Y-m-d H:i:s' ) .  "\n" ;
?>

以上例程的输出类似于:

Current time: 2010-04-23 10:29:35
Format: Y-m-d; 2009-02-15 10:29:35
Format: Y-m-d H:i:s; 2009-02-15 15:16:17
Format: Y-m-!d H:i:s; 1970-01-15 15:16:17
Format: !d; 1970-01-15 00:00:00

参见

  • DateTime::__construct() - Returns new DateTime object
  • DateTime::getLastErrors() - Returns the warnings and errors
  • checkdate() - 验证一个格里高里日期
  • strptime() - 解析由 strftime 生成的日期/时间

用户评论:

[#1] Albie at aveit dot org [2015-11-22 18:58:45]

If you want to safely compare equality of a DateTime object without explicitly providing the time portion make use of the ! format character.

<?php
$date1 
DateTime::createFromFormat('!Y-m-d''2012-10-17');
sleep(2);
$date2 DateTime::createFromFormat('!Y-m-d''2012-10-17');

?>


If you omit the ! format character without explicitly providing the time portion your timestamp which will include the current system time in the stamp.

<?php
$date1 
DateTime::createFromFormat('Y-m-d''2012-10-17');
sleep(2);
$date2 DateTime::createFromFormat('Y-m-d''2012-10-17');
var_dump($date1 == $date2); //will be false
var_dump($date1 >= $date2); //will be false
var_dump($date1 $date2); //will be true
?>

[#2] chernomyrdin at gmail dot com [2015-11-19 11:39:15]

<?php
$date 
DateTime::createFromFormat('U.u'microtime(TRUE));
var_dump($date->format('Y-m-d H:i:s.u')); 
?>

will print: 2015-11-19 11:37:29.125300 (the current time with microseconds)

[#3] jplevene [2015-06-12 15:09:43]

To convert an email header date use the following (important, notice the * at the end)

$date = DateTime::createFromFormat('D, d M Y H:i:s O *', $email_date);

Some dates in email headers can be formatted as:
Fri, 12 Jun 2015 13:53:37 +0000 (UTC)

The "(UTC)" at the end of the date causes an error and will return a result of false unless the * is at the end.

[#4] SeliusX [2015-01-30 14:37:46]

Creating timestamps to the day can result in hidden bugs cause hours are taken from now:

Example:
$newDateTime = DateTime::createFromFormat('Y-m-d', '2014-12-10');
$newDateTime->format('H') != '00';

Better use time too or erase the values later on:
$newDateTime = DateTime::createFromFormat('Y-m-d h:i', '2014-12-10 00:00');
or:
$newDateTime = DateTime::createFromFormat(''Y-m-d', '2014-12-10');
$newDateTime->setTime(0, 0);

[#5] ELPI [2014-10-31 10:04:17]

It can be confusing creating new DateTime from timestamp when your default timezone (date.timezone) is different from UTC and you are used to date()-function.

date()-function automatically uses your current timezone setting but DateTime::createFromFormat (or DateTime constructor) does not (it ignores tz-parameter).

You can get same results as date() by setting the timezone after object creation.

<?php
$ts 
1414706400;
$date1 date("Y-m-d H:i"$ts);
$date2 DateTime::createFromFormat("U"$ts)->setTimeZone(new DateTimeZone(date_default_timezone_get()))->format("Y-m-d H:i");
//$date1===$date2
?>

[#6] nicodoggie at gmail dot com [2014-06-25 13:20:07]

I've found that on PHP 5.5.13 (not sure if it happens on other versions) if you enter a month larger than 12 on a format that takes numeric months, the result will be a DateTime object with its month equal to the number modulo 12 instead of returning false.

<?php
var_dump
(DateTime::createFromFormat('Y-m-d''2013-22-01'));
?>


results in:
class DateTime#4 (3) {
  public $date =>
  string(19) "2014-10-01 13:05:05"
  public $timezone_type =>
  int(3)
  public $timezone =>
  string(3) "UTC"
}

[#7] d dot shankarnarayana at gmail dot com [2014-03-24 18:46:43]

Say if there is a string with  $date = "today is 2014 January 1";   and you need to extract "2014 January" using DateTime::createFromFormat().  As you can see in the string there is something odd like "today is" .Since that string (today is) does not correspond to a date format, we need to escape that. 

In this case, each and every character on that string has to be escaped as shown below.

The code.

<?php
$paragraph = "today is 2014 January 1";
$date = DateTime::createFromFormat('\t\o\d\a\y \i\s Y F j', $paragraph);
echo $date->format('Y F'); //"prints" 2014 January

- Shankar Damodaran

[#8] mail at marcel-juenemann dot de [2013-01-17 17:24:23]

Note that the U option does not support negative timestamps (before 1970). You have to use date for that.

[#9] falundir at gmail dot com [2012-10-17 12:03:16]

Be warned that DateTime object created without explicitely providing the time portion will have the current time set instead of 00:00:00.

<?php
$date 
DateTime::createFromFormat('Y-m-d''2012-10-17');
var_dump($date->format('Y-m-d H:i:s')); //will print 2012-10-17 13:57:34 (the current time)
?>


That's also why you can't safely compare equality of such DateTime objects:

<?php
$date1 
DateTime::createFromFormat('Y-m-d''2012-10-17');
sleep(2);
$date2 DateTime::createFromFormat('Y-m-d''2012-10-17');
var_dump($date1 == $date2); //will be false
var_dump($date1 >= $date2); //will be false
var_dump($date1 $date2); //will be true
?>

[#10] thomas dot ribiere at allgoob dot com [2012-08-30 15:46:35]

Not a bug, but a strange issue today 2012-08-30 :

<?php
$date 
"2011-02";
echo 
$date."\n";
$d DateTime::createFromFormat("Y-m",$date);
echo 
$d->format("Y-m");
?>

will display : 
2011-02
2011-03

It's because there is no 2011-02-30, so datetime will take march insteed of february ...

To fix it :
<?php 
$date 
"2011-02";
echo 
$date."\n";
$d DateTime::createFromFormat("Y-m-d",$date."-01");
echo 
$d->format("Y-m");
?>

[#11] kamil dot wegrzynowicz at baobaz dot com [2012-02-10 08:05:50]

It seems that a pipe ('|') option in formating string works only with PHP version 5.3.7 and newer. We had an issue with it on versions 5.3.2, 5.3.3, 5.3.6. Yet it was fine with 5.3.8 and 5.3.10.

By short example:
<?php
$timezone 
= new DateTimeZone('UTC');
$dateTime DateTime::createFromFormat('dmY|''01011972'$timezone);
//$dateTime is FALSE in PHP v <5.3.8
?>


Instead we used a workaround:
<?php
$dateTime 
DateTime::createFromFormat('dmY''01011972'$timezone);
$dateTime->format('Y-m-d 00:00:00');
?>

which works fine.

====

Modified by admin to correct for version (5.3.7 not 5.3.8)

[#12] Aurelien Marchand [2011-03-29 07:13:55]

Beware specifying a timezone in the format as it will take precedence over the DateTimeZone object.

<?php
$timezone 
"UTC"// or any other valid name for a timezone
$dDateTime::createFromFormat("Y-m-d H:i:s T","2011-11-06 00:00:00 EDT",new DateTimeZone($timezone));
echo 
$d->format("Y-m-d H:i:s T - U");
// returns "2011-11-06 00:00:00 EDT - 1320552000"
// specifying $timezone = "Pacific/Honolulu"; would return the same string
?>


This gets hairy when you are playing with transition from summer time to winter time! For instance, in Toronto, the time change happens on 2011-11-06. One second after 01:59:59 (EDT), the time becomes 01:00:00 (EST), or 1320559200 in Unix timestamp.

However, notice the following:
<?php
$d 
DateTime::createFromFormat("Y-m-d H:i:s","2011-11-06 01:00:00",new DateTimeZone("EST"));
echo 
$d->format("Y-m-d H:i:s T U");
// returns "2011-11-06 01:00:00 EDT 1320555600" instead of "2011-11-06 01:00:00 EST 1320559200"

// so the correct way is to do:
$d DateTime::createFromFormat("Y-m-d H:i:s T","2011-11-06 01:00:00 EST",new DateTimeZone($timezone)); // set $timezone to any valid string for DateTimeZone, it doesn't matter
echo $d->format("Y-m-d H:i:s T U");
// returns "2011-11-06 01:00:00 EST - 1320559200" as wanted

?>

[#13] klugg at tlen dot pl [2011-03-14 09:52:30]

In order to use a DateTimeZone, don't enter one of the DateTimeZone::Europe, DateTimeZone::Asia etc. constants, but create a DateTimeZone object with verbal timezone name passed as a string:
<?php
$eventDate 
DateTime::createFromFormat('m/d/y h:i''02/26/11 08:00', new DateTimeZone('Europe/Warsaw'));
echo 
date_format($eventDate'Y-m-d'); //prints "2011-02-26"

?>

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