php 날짜, 시간 관련 함수

time() 은 1970년 1월 1일 0시 0분 0초부터 지금까지 지나온 초를 정수형태로 리턴해주는 함수 입니다.

int time ( void )

<?php

$now_timestamp = time();

echo $now_titmestamp;

?>

결과는 아래와 유사하게 표시될 겁니다.

1356066385

date()는 time()으로 구해진 타임스탬프를 읽기 좋게 포맷팅해 주는 함수 입니다.

string date ( string $format [, int $timestamp = time() ] )

게시판 등에서 글 작성한 시각을 time()으로 구해서 DB에 저장하고, 이후 표시해줄 때, date()를 이용해서 적절히 포맷팅을 해서 보여주면 되겠습니다.

date("Y-m-d h:i:s",$data['reg_date'])

위 포맷으로 표시하면, 아래의 형태를 나타냅니다.

2012-12-21 02:06:25

아래 표는 포맷팅에 사용할 수 있는 문자에 관한 설명입니다.

formatcharacter	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 (added in PHP 5.1.0)	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 (added in PHP 4.1.0)	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 year number. 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. (added in PHP 5.1.0)	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 (added in PHP 5.2.2). Note that date() will always generate 000000 since it takes an integer parameter, whereas DateTime::format() does support microseconds.	Example: 654321
Timezone	---	---
e	Timezone identifier (added in PHP 5.1.0)	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) in hours	Example: +0200
P	Difference to Greenwich time (GMT) with colon between hours and minutes (added in PHP 5.1.3)	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 (added in PHP 5)	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()

mktime()은 날짜정보를 입력해서 타임스탬프를 구할 수 있는 함수입니다.

int mktime ([ int $hour = date("H") [, int $minute = date("i") [, int $second = date("s") [, int $month = date("n") [, int $day = date("j") [, int $year = date("Y") [, int $is_dst = -1 ]]]]]]] )

시간, 분, 초, 월, 일, 년의 순서대로 입력해서 타임스탬프를 구할 수 있습니다.

<?php
            $t = mktime(21, 21, 21, 12, 21, 2012);
            echo $t;
 ?>

마야달력의 마지막 순간의 타임스탬프는 아래와 같네요. ^^;

1356092481

출처 : http://zzaps.tistory.com/51