參數

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 format is parsed from left to right, which means that in some situations the order in which the format characters are present effects the result. In the case of z (the day of the year), it is required that a year has already been parsed, for example through the Y or y characters.

Letters that are used for parsing numbers allow a wide range of values, outside of what the logical range would be. For example, the d (day of the month) accepts values in the range from 00 to 99. The only constraint is on the amount of digits. The date/time parser's overflow mechanism is used when out-of-range values are given. The examples below show some of this behaviour.

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. (2 digit numbers higher than the number of days in the month are accepted, in which case they will make the month overflow. For example using 33 with January, means February 2nd)
D and l	A textual representation of a day	Mon through Sun or Sunday through Saturday. If the day name given is different then the day name belonging to a parsed (or default) date is different, then an overflow occurs to the next date with the given day name. See the examples below for an explanation.
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); must be preceded by Y or y.	0 through 365. (3 digit numbers higher than the numbers in a year are accepted, in which case they will make the year overflow. For example using 366 with 2022, means January 2nd, 2023)
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. (2 digit numbers higher than 12 are accepted, in which case they will make the year overflow. For example using 13 means January in the next year)
Year	---	---
X and x	A full numeric representation of a year, up to 19 digits, optionally prefixed by + or -	Examples: 0055, 787, 1999, -2003, +10191
Y	A full numeric representation of a year, up to 4 digits	Examples: 0055, 787, 1999, 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 (2 digit numbers higher than 12 are accepted, in which case they will make the day overflow. For example using 14 means 02 in the next AM/PM period)
G and H	24-hour format of an hour with or without leading zeros	0 through 23 or 00 through 23 (2 digit numbers higher than 24 are accepted, in which case they will make the day overflow. For example using 26 means 02:00 the next day)
i	Minutes with leading zeros	00 to 59. (2 digit numbers higher than 59 are accepted, in which case they will make the hour overflow. For example using 66 means :06 the next hour)
s	Seconds, with leading zeros	00 through 59 (2 digit numbers higher than 59 are accepted, in which case they will make the minute overflow. For example using 90 means :30 the next minute)
v	Fraction in milliseconds (up to three digits)	Example: 12 (0.12 seconds), 345 (0.345 seconds)
u	Fraction in microseconds (up to six digits)	Example: 45 (0.45 seconds), 654321 (0.654321 seconds)
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 timezone information) to zero-like values ( 0 for hour, minute, second and fraction, 1 for month and day, 1970 for year and UTC for timezone information)	Without !, all fields will be set to the current date and time.
|	Resets all fields (year, month, day, hour, minute, second, fraction and timezone information) to zero-like values 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 DateTimeImmutable::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 DateTimeImmutable::getLastErrors().

To include literal characters in format, you have to escape them with a backslash (\).

If format does not contain the character ! then portions of the generated date/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 date/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.

If any time character is parsed, then all other time-related fields are set to "0", unless also parsed.

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

datetime

String representing the time.

timezone

A DateTimeZone object representing the desired time zone.

If timezone is omitted or null and datetime contains no timezone, the current timezone will be used.

注意:

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