date
(PHP 4, PHP 5, PHP 7)
date — 格式化一个本地时间/日期
说明
date ( string $format
[, int $timestamp
] ) : string
Tip自 PHP 5.1.1 起有几个有用的常量可用作标准的日期/时间格式来指定 format
参数。
Note:
有效的时间戳典型范围是格林威治时间 1901 年 12 月 13 日 20:45:54 到 2038 年 1 月 19 日 03:14:07。(此范围符合 32 位有符号整数的最小值和最大值)。不过在 PHP 5.1 之前此范围在某些系统(如 Windows)中限制为从 1970 年 1 月 1 日到 2038 年 1 月 19 日。
Note:
要将字符串表达的时间转换成时间戳,应该使用 strtotime()。此外一些数据库有一些函数将其时间格式转换成时间戳(例如 MySQL 的 » UNIX_TIMESTAMP 函数)。
格式字串可以识别以下 format
参数的字符串format 字符 | 说明 | 返回值例子 |
---|
日 | --- | --- |
d | 月份中的第几天,有前导零的 2 位数字 | 01 到 31 |
D | 星期中的第几天,文本表示,3 个字母 | Mon 到 Sun |
j | 月份中的第几天,没有前导零 | 1 到 31 |
l(“L”的小写字母) | 星期几,完整的文本格式 | Sunday 到 Saturday |
N | ISO-8601 格式数字表示的星期中的第几天(PHP 5.1.0 新加) | 1(表示星期一)到 7(表示星期天) |
S | 每月天数后面的英文后缀,2 个字符 | st,nd,rd 或者 th。可以和 j 一起用 |
w | 星期中的第几天,数字表示 | 0(表示星期天)到 6(表示星期六) |
z | 年份中的第几天 | 0 到 365 |
星期 | --- | --- |
W | ISO-8601 格式年份中的第几周,每周从星期一开始(PHP 4.1.0 新加的) | 例如:42(当年的第 42 周) |
月 | --- | --- |
F | 月份,完整的文本格式,例如 January 或者 March | January 到 December |
m | 数字表示的月份,有前导零 | 01 到 12 |
M | 三个字母缩写表示的月份 | Jan 到 Dec |
n | 数字表示的月份,没有前导零 | 1 到 12 |
t | 指定的月份有几天 | 28 到 31 |
年 | --- | --- |
L | 是否为闰年 | 如果是闰年为 1,否则为 0 |
o | ISO-8601 格式年份数字。这和 Y 的值相同,只除了如果 ISO 的星期数(W)属于前一年或下一年,则用那一年。(PHP 5.1.0 新加) | Examples: 1999 or 2003 |
Y | 4 位数字完整表示的年份 | 例如:1999 或 2003 |
y | 2 位数字表示的年份 | 例如:99 或 03 |
时间 | --- | --- |
a | 小写的上午和下午值 | am 或 pm |
A | 大写的上午和下午值 | AM 或 PM |
B | Swatch Internet 标准时 | 000 到 999 |
g | 小时,12 小时格式,没有前导零 | 1 到 12 |
G | 小时,24 小时格式,没有前导零 | 0 到 23 |
h | 小时,12 小时格式,有前导零 | 01 到 12 |
H | 小时,24 小时格式,有前导零 | 00 到 23 |
i | 有前导零的分钟数 | 00 到 59> |
s | 秒数,有前导零 | 00 到 59> |
u | 毫秒 (PHP 5.2.2 新加)。需要注意的是 date() 函数总是返回 000000 因为它只接受 integer 参数, 而 DateTime::format() 才支持毫秒。 | 示例: 654321 |
时区 | --- | --- |
e | 时区标识(PHP 5.1.0 新加) | 例如:UTC,GMT,Atlantic/Azores |
I | 是否为夏令时 | 如果是夏令时为 1,否则为 0 |
O | 与格林威治时间相差的小时数 | 例如:+0200 |
P | 与格林威治时间(GMT)的差别,小时和分钟之间有冒号分隔(PHP 5.1.3 新加) | 例如:+02:00 |
T | 本机所在的时区 | 例如:EST,MDT(【译者注】在 Windows 下为完整文本格式,例如“Eastern Standard Time”,中文版会显示“中国标准时间”)。 |
Z | 时差偏移量的秒数。UTC 西边的时区偏移量总是负的,UTC 东边的时区偏移量总是正的。 | -43200 到 43200 |
完整的日期/时间 | --- | --- |
c | ISO 8601 格式的日期(PHP 5 新加) | 2004-02-12T15:19:21+00:00 |
r | RFC 822 格式的日期 | 例如:Thu, 21 Dec 2000 16:01:07 +0200 |
U | 从 Unix 纪元(January 1 1970 00:00:00 GMT)开始至今的秒数 | 参见 time() |
格式字串中不能被识别的字符将原样显示。Z 格式在使用 gmdate() 时总是返回 0。
Example #1 date() 例子
<?php
// 设定要用的默认时区。自 PHP 5.1 可用
date_default_timezone_set('UTC');
// 输出类似:Monday
echo date("l");
// 输出类似:Monday 15th of August 2005 03:12:46 PM
echo date('l dS \of F Y h:i:s A');
// 输出:July 1, 2000 is on a Saturday
echo "July 1, 2000 is on a " . date("l", mktime(0, 0, 0, 7, 1, 2000));
/* 在格式参数中使用常量 */
// 输出类似:Wed, 25 Sep 2013 15:28:57 -0700
echo date(DATE_RFC2822);
// 输出类似:2000-07-01T00:00:00+00:00
echo date(DATE_ATOM, mktime(0, 0, 0, 7, 1, 2000));
?>
在格式字串中的字符前加上反斜线来转义可以避免它被按照上表解释。如果加上反斜线后的字符本身就是一个特殊序列,那还要转义反斜线。
Example #2 在 date() 中转义字符
<?php
// prints something like: Wednesday the 15th
echo date("l \\t\h\e jS");
?>
可以把 date() 和 mktime() 函数结合使用来得到未来或过去的日期。
Example #3 date() 和 mktime() 例子
<?php
$tomorrow = mktime(0, 0, 0, date("m") , date("d")+1, date("Y"));
$lastmonth = mktime(0, 0, 0, date("m")-1, date("d"), date("Y"));
$nextyear = mktime(0, 0, 0, date("m"), date("d"), date("Y")+1);
?>
Note:
由于夏令时的缘故,这种方法比简单地在时间戳上加减一天或者一个月的秒数更可靠。
一些使用 date() 格式化日期的例子。注意要转义所有其它的字符,因为目前有特殊含义的字符会产生不需要的结果,而其余字符在 PHP 将来的版本中可能会被用上。当转义时,注意用单引号以避免类似 \n 的字符变成了换行符。
Example #4 date() 格式举例
<?php
// 假定今天是:March 10th, 2001, 5:16:18 pm
$today = date("F j, Y, g:i a"); // March 10, 2001, 5:16 pm
$today = date("m.d.y"); // 03.10.01
$today = date("j, n, Y"); // 10, 3, 2001
$today = date("Ymd"); // 20010310
$today = date('h-i-s, j-m-y, it is w Day z '); // 05-16-17, 10-03-01, 1631 1618 6 Fripm01
$today = date('\i\t \i\s \t\h\e jS \d\a\y.'); // It is the 10th day.
$today = date("D M j G:i:s T Y"); // Sat Mar 10 15:16:08 MST 2001
$today = date('H:m:s \m \i\s\ \m\o\n\t\h'); // 17:03:17 m is month
$today = date("H:i:s"); // 17:16:17
$today = date("Y-m-d H:i:s"); // 2001-03-10 17:16:18 (MySQL DATETIME 格式)
?>
要格式化其它语种的日期,应该用 setlocale() 和 strftime() 函数来代替 date()。
参见 getlastmod(),gmdate(),mktime(),strftime() 和 time()。
参数
format
输出的日期 string 格式。 参见下文中的 格式化选项。 同时,还可以使用 预定义日期常量 ,例如:常量 DATE_RSS
表示格式化字符串 'D, d M Y H:i:s'。
format
参数字符串中可识别下列字符format 字符 | 描述 | 返回值示例 |
---|
天 | --- | --- |
d | 一个月中的第几天,有前导 0 的 2 位数字 | 从 01 到 31 |
D | 3 个字符表示的星期几 | 从 Mon 到 Sun |
j | 一个月中的第几天,无前导 0 | 从 1 到 31 |
l(lowercase 'L') | 星期几,英文全称 | 从 Sunday 到 Saturday |
N | ISO-8601 规定的数字表示的星期几(PHP 5.1.0 新加 ) | 从 1 (表示星期一)到 7 (表示星期日) |
S | 一个月中的第几天,带有 2 个字符表示的英语序数词。 | st, nd, rd 或者 th。 可以和 j联合使用。 |
w | 数字表示的星期几 | 从 0 (星期日) 到 6 (星期六) |
z | 一年中的第几天,从 0 开始计数 | 从 0 到 365 |
周 | --- | --- |
W | ISO-8601 规范的一年中的第几周,周一视为一周开始。(PHP 4.1.0 新加) | 示例: 42 (本年第42周) |
月 | --- | --- |
F | 月份英文全拼,例如:January 或 March | 从 January 到 December |
m | 带有 0 前导的数字表示的月份 | 从 01 到 12 |
M | 3 个字符表示的月份的英文简拼 | 从 Jan 到 Dec |
n | 月份的数字表示,无前导 0 | 1 through 12 |
t | 给定月份中包含多少天 | 从 28 到 31 |
年 | --- | --- |
L | 是否为闰年 | 如果是闰年,则返回 1,反之返回 0。 |
o | ISO-8601 规范的年份,同 Y 格式。有一种情况除外:当 ISO 的周数(W)属于前一年或者后一年时,会返回前一年或者后一年的年份数字表达。 属于前一年或者后一年时,会返回前一年或者后一年的年份数字表达。 (PHP 5.1.0 新加) | 示例:1999 或 2003 |
Y | 4 位数字的年份 | 示例:1999 或 2003 |
y | 2 位数字的年份 | 示例: 99 或 03 |
时间 | --- | --- |
a | 上午还是下午,2 位小写字符 | am 或 pm |
A | 上午还是下午,2 位大写字符 | AM 或 PM |
B | 斯沃琪因特网时间 | 从 000 到 999 |
g | 小时,12时制,无前导 0 | 从 1 到 12 |
G | 小时,24时制,无前导 0 | 从 0 到 23 |
h | 小时,12时制,有前导 0 的 2 位数字 | 从 01 到 12 |
H | 小时,24时制,有前导 0 的 2 位数字 | 00 through 23 |
i | 分钟,有前导 0 的 2 位数字 | 从 00 到 59 |
s | 秒,有前导 0 的 2 位数字 | 从 00 到 59 |
u | 毫秒 (PHP 5.2.2 新加) | 示例: 654321 |
时区 | --- | --- |
e | 时区标识(PHP 5.1.0 新加) | 示例: UTC, GMT, Atlantic/Azores |
I (大写字母 i) | 是否夏令时 | 如果是夏令时则返回 1,反之返回 0。 |
O | 和格林威治时间(GMT)的时差,以小时为单位 | 示例: +0200 |
P | 和格林威治时间(GMT)的时差,包括小时和分钟,小时和分钟之间使用冒号(:)分隔(PHP 5.1.3 新加) | 示例: +02:00 |
T | 时区缩写 | 示例:EST, MDT... |
Z | 以秒为单位的时区偏移量。UTC 以西的时区返回负数,UTC 以东的时区返回正数。 | 从 -43200 到 50400 |
完整的日期/时间 | --- | --- |
c | ISO 8601 日期及时间(PHP 5 新加) | 2004-02-12T15:19:21+00:00 |
r | » RFC 2822 格式的日期和时间 | 示例:Thu, 21 Dec 2000 16:01:07 +0200 |
U | 自 1970 年 1 月 1 日 0 时 0 分 0 秒(GMT 时间)以来的时间,以秒为单位 | 参见time() |
格式化字符串中的不可识别字符将原样输出。 当使用 gmdate() 函数时, Z 格式永远返回 0。
Note:
由于本函数仅接受 integer 类型的时间戳参数,所以 u 格式仅在使用 date_format() 函数并且使用date_create() 函数创建时间戳时才是有用的。
timestamp
可选的 timestamp
参数是一个 integer 的 Unix 时间戳,如未指定,参数值默认为当前本地时间。也就是说,其值默认为 time() 的返回值。
返回值
返回格式化后的日期时间的字符串表达。 如果 timestamp
参数不是一个有效数值,则返回 FALSE
并引发 E_WARNING
级别的错误。
范例
Example #5 date() 函数示例
<?php
// 设置默认时区。PHP 5.1 之后版本可用
date_default_timezone_set('UTC');
// 输出类似: Monday
echo date("l");
// 输出类似:Monday 8th of August 2005 03:12:46 PM
echo date('l jS \of F Y h:i:s A');
// 输出:July 1, 2000 is on a Saturday
echo "July 1, 2000 is on a " . date("l", mktime(0, 0, 0, 7, 1, 2000));
/* 使用格式常量 */
// 输出类似: Mon, 15 Aug 2005 15:12:46 UTC
echo date(DATE_RFC822);
// 输出类似:2000-07-01T00:00:00+00:00
echo date(DATE_ATOM, mktime(0, 0, 0, 7, 1, 2000));
?>
可以使用反斜线进行转义来阻止函数解析格式字符串中的可识别字符。 如果反斜线和要转义的字符连在一起依然是一个有效的字符序列,那么需要对 反斜线再次进行转义。
Example #6 对 date() 函数中的格式字符串进行转义
<?php
// 输出类似: Wednesday the 15th
echo date('l \t\h\e jS');
?>
可以联合使用 date() 和 mktime() 函数 来构造之前或者之后的日期时间。
Example #7 date() 和 mktime() 联合使用示例
<?php
$tomorrow = mktime(0, 0, 0, date("m") , date("d")+1, date("Y"));
$lastmonth = mktime(0, 0, 0, date("m")-1, date("d"), date("Y"));
$nextyear = mktime(0, 0, 0, date("m"), date("d"), date("Y")+1);
?>
Note:
由于存在夏令时时间, 所以此方案相对于直接在时间戳上加/减秒数 要更加可靠。
date() 函数格式化的一些示例。 需要注意的是,即使是对于当前来说并不具有特殊含义的字符, 也要像对待具有特殊含义的字符那样进行转义,以避免函数返回非预期的值。 因为可能在将来的 PHP 版本中,这些字符会被赋予特殊的含义。 进行转义的时候,请确保使用单引号,以避免 \n 被解释为换行符号。
Example #8 date() 函数格式化
<?php
// 假设今天是 2001 年 3 月 10 日下午 5 点 16 分 18 秒,
// 并且位于山区标准时间(MST)时区
$today = date("F j, Y, g:i a"); // March 10, 2001, 5:16 pm
$today = date("m.d.y"); // 03.10.01
$today = date("j, n, Y"); // 10, 3, 2001
$today = date("Ymd"); // 20010310
$today = date('h-i-s, j-m-y, it is w Day'); // 05-16-18, 10-03-01, 1631 1618 6 Satpm01
$today = date('\i\t \i\s \t\h\e jS \d\a\y.'); // it is the 10th day.
$today = date("D M j G:i:s T Y"); // Sat Mar 10 17:16:18 MST 2001
$today = date('H:m:s \m \i\s\ \m\o\n\t\h'); // 17:03:18 m is month
$today = date("H:i:s"); // 17:16:18
?>
如果需要将日期时间格式化为其他语言,你应该使用 setlocale() 和 strftime() 函数 来替代 date() 函数。
Jimmy ¶7 years ago
Things to be aware of when using week numbers with years.
<?php
echo date("YW", strtotime("2011-01-07")); echo date("YW", strtotime("2011-12-31")); echo date("YW", strtotime("2011-01-01")); ?>
BUT
<?php
echo date("oW", strtotime("2011-01-07")); echo date("oW", strtotime("2011-12-31")); echo date("oW", strtotime("2011-01-01")); ?>
Reason:
Y is year from the date
o is ISO-8601 year number
W is ISO-8601 week number of year
Conclusion:
if using 'W' for the week number use 'o' for the year.
mirco dot babin at gmail dot com ¶5 months ago
One important thing you should remember is that the timestamp value returned by time() is time-zone agnostic and gets the number of seconds since 1 January 1970 at 00:00:00 UTC. This means that at a particular point in time, this function will return the same value in the US, Europe, India, Japan, ...
date() will format a time-zone agnostic timestamp according to the default timezone set with date_default_timezone_set(...). Local time. If you want to output as UTC time use:
<?php
function dateUTC($format, $timestamp = null)
{
if ($timestamp === null) $timestamp = time();
$tz = date_default_timezone_get();
date_default_timezone_set('UTC');
$result = date($format, $timestamp);
date_default_timezone_set($tz);
return $result;
}
/>
matthew dot hotchen at worldfirst dot com ¶5 years ago
FYI: there's a list of constants with predefined formats on the DateTime object, for example instead of outputting ISO 8601 dates with:
<?php
echo date('c');
?>
or
<?php
echo date('Y-m-d\TH:i:sO');
?>
You can use
<?php
echo date(DateTime::ISO8601);
?>
instead, which is much easier to read.
adityabhai at gmail dot com ¶5 years ago
For Microseconds, we can get by following:
echo date('Ymd His'.substr((string)microtime(), 1, 8).' e');
Thought, it might be useful to someone !
ivijan dot stefan at gmail dot com ¶4 years ago
If you have a problem with the different time zone, this is the solution for that.
<?php
$defaultTimeZone='UTC';
if(date_default_timezone_get()!=$defaultTimeZone)) date_default_timezone_set($defaultTimeZone);
function _date($format="r", $timestamp=false, $timezone=false)
{
$userTimezone = new DateTimeZone(!empty($timezone) ? $timezone : 'GMT');
$gmtTimezone = new DateTimeZone('GMT');
$myDateTime = new DateTime(($timestamp!=false?date("r",(int)$timestamp):date("r")), $gmtTimezone);
$offset = $userTimezone->getOffset($myDateTime);
return date($format, ($timestamp!=false?(int)$timestamp:$myDateTime->format('U')) + $offset);
}
echo 'System Date/Time: '.date("Y-m-d | h:i:sa").'<br>';
echo 'New York Date/Time: '._date("Y-m-d | h:i:sa", false, 'America/New_York').'<br>';
echo 'Belgrade Date/Time: '._date("Y-m-d | h:i:sa", false, 'Europe/Belgrade').'<br>';
echo 'Belgrade Date/Time: '._date("Y-m-d | h:i:sa", 514640700, 'Europe/Belgrade').'<br>';
?>
This is the best and fastest solution for this problem. Working almost identical to date() function only as a supplement has the time zone option.
FiraSEO ¶6 years ago
this how you make an HTML5 <time> tag correctly
<?php
echo '<time datetime="'.date('c').'">'.date('Y - m - d').'</time>';
?>
in the "datetime" attribute you should put a machine-readable value which represent time , the best value is a full time/date with ISO 8601 ( date('c') ) ,,, the attr will be hidden from users
and it doesn't really matter what you put as a shown value to the user,, any date/time format is okay !
This is very good for SEO especially search engines like Google .
bruslbn at gmail dot com ¶1 year ago
In order to define leap year you must considre not only that year can be divide by 4!
The correct alghoritm is:
if (year is not divisible by 4) then (it is a common year)
else if (year is not divisible by 100) then (it is a leap year)
else if (year is not divisible by 400) then (it is a common year)
else (it is a leap year)
So the code should look like this:
if($year%4 == 0 && $year%100 != 0) {
$leapYear = 1;
} elseif($year%400 == 0) {
$leapYear = 1;
} else {
$leapYear = 0;
}
david dot thomas at elliott-thomas dot com dot au ¶2 years ago
Prior to PHP 5.6.23, Relative Formats for the start of the week aligned with PHP's (0=Sunday,6=Saturday). Since 5.6.23, Relative Formats for the start of the week align with ISO-8601 (1=Monday,7=Sunday). (http://php.net/manual/en/datetime.formats.relative.php)
This can produce different, and seemingly incorrect, results depending on your PHP version and your choice of 'w' or 'N' for the Numeric representation of the day of the week:
<?php
echo "Today is Sun 2 Oct 2016, day ",date('w',strtotime('2016-10-02'))," of this week. ";
echo "Day ",date('w',strtotime('2016-10-02 Monday next week'))," of next week is ",date('d M Y',strtotime('2016-10-02 Monday next week')),"<br />";
echo "Today is Sun 2 Oct 2016, day ",date('N',strtotime('2016-10-02'))," of this week. ";
echo "Day ",date('w',strtotime('2016-10-02 Monday next week'))," of next week is ",date('d M Y',strtotime('2016-10-02 Monday next week'));
?>
Prior to PHP 5.6.23, this results in:
Today is Sun 2 Oct 2016, day 0 of this week. Day 1 of next week is 10 Oct 2016
Today is Sun 2 Oct 2016, day 7 of this week. Day 1 of next week is 10 Oct 2016
Since PHP 5.6.23, this results in:
Today is Sun 2 Oct 2016, day 0 of this week. Day 1 of next week is 03 Oct 2016
Today is Sun 2 Oct 2016, day 7 of this week. Day 1 of next week is 03 Oct 2016
Anonymous ¶3 years ago
If timestamp is a string, date converts it to an integer in a possibly unexpected way:
<?php
echo (int)'0x10'; echo intval('0x10'); echo date('s', '0x10'); echo date('s', '010'); ?>
(PHP 5.6.16)
rc at macshot dot de ¶2 years ago
At least in PHP 5.5.38 date('j.n.Y', 2222222222) gives a result of 2.6.2040.
So date is not longer limited to the minimum and maximum values for a 32-bit signed integer as timestamp.
Anonymous ¶5 years ago
It's common for us to overthink the complexity of date/time calculations and underthink the power and flexibility of PHP's built-in functions. Consider http://php.net/manual/en/function.date.php#108613
<?php
function get_time_string($seconds)
{
return date('H:i:s', strtotime("2000-01-01 + $seconds SECONDS"));
}
bruslbn at gmail dot com ¶1 year ago
In order to define leap year you must considre not only that year can be divide by 4!
The correct alghoritm is:
if (year is not divisible by 4) then (it is a common year)
else if (year is not divisible by 100) then (it is a leap year)
else if (year is not divisible by 400) then (it is a common year)
else (it is a leap year)
So the code should look like this:
if($year%4 == 0 && $year%100 != 0) {
$leapYear = 1;
} elseif($year%400 == 0) {
$leapYear = 1;
} else {
$leapYear = 0;
}
ghotinet ¶8 years ago
Most spreadsheet programs have a rather nice little built-in function called NETWORKDAYS to calculate the number of business days (i.e. Monday-Friday, excluding holidays) between any two given dates. I couldn't find a simple way to do that in PHP, so I threw this together. It replicates the functionality of OpenOffice's NETWORKDAYS function - you give it a start date, an end date, and an array of any holidays you want skipped, and it'll tell you the number of business days (inclusive of the start and end days!) between them.
I've tested it pretty strenuously but date arithmetic is complicated and there's always the possibility I missed something, so please feel free to check my math.
The function could certainly be made much more powerful, to allow you to set different days to be ignored (e.g. "skip all Fridays and Saturdays but include Sundays") or to set up dates that should always be skipped (e.g. "skip July 4th in any year, skip the first Monday in September in any year"). But that's a project for another time.
<?php
function networkdays($s, $e, $holidays = array()) {
if ($s > $e)
return networkdays($e, $s, $holidays);
$sd = date("N", $s);
$ed = date("N", $e);
$w = floor(($e - $s)/(86400*7)); if ($ed >= $sd) { $w--; } $nwd = max(6 - $sd, 0); $nwd += min($ed, 5); $nwd += $w * 5; foreach ($holidays as $h) {
$h = strtotime($h);
if ($h > $s && $h < $e && date("N", $h) < 6)
$nwd--;
}
return $nwd;
}
$start = strtotime("1 January 2010");
$end = strtotime("13 December 2010");
$holidays = array();
$holidays[] = "4 July 2010"; $holidays[] = "6 September 2010"; echo networkdays($start, $end, $holidays); ?>
Or, if you just want to know how many work days there are in any given year, here's a quick function for that one:
<?php
function workdaysinyear($y) {
$j1 = mktime(0,0,0,1,1,$y);
if (date("L", $j1)) {
if (date("N", $j1) == 6)
return 260;
elseif (date("N", $j1) == 5 or date("N", $j1) == 7)
return 261;
else
return 262;
}
else {
if (date("N", $j1) == 6 or date("N", $j1) == 7)
return 260;
else
return 261;
}
}
?>
SpikeDaCruz ¶13 years ago
The following function will return the date (on the Gregorian calendar) for Orthodox Easter (Pascha). Note that incorrect results will be returned for years less than 1601 or greater than 2399. This is because the Julian calendar (from which the Easter date is calculated) deviates from the Gregorian by one day for each century-year that is NOT a leap-year, i.e. the century is divisible by 4 but not by 10. (In the old Julian reckoning, EVERY 4th year was a leap-year.)
This algorithm was first proposed by the mathematician/physicist Gauss. Its complexity derives from the fact that the calculation is based on a combination of solar and lunar calendars.
<?php
function getOrthodoxEaster($date){
$year = date("Y", $date);
$r1 = $year % 19;
$r2 = $year % 4;
$r3 = $year % 7;
$ra = 19 * $r1 + 16;
$r4 = $ra % 30;
$rb = 2 * $r2 + 4 * $r3 + 6 * $r4;
$r5 = $rb % 7;
$rc = $r4 + $r5;
return strtotime("3 April $year + $rc days");
}
?>
Bas Vijfwinkel ¶7 years ago
Note that some formatting options are different from MySQL.
For example using a 24 hour notation without leading zeros is the option '%G' in PHP but '%k' in MySQL.
When using dynamically generated date formatting string, be careful to generate the correct options for either PHP or MySQL.
bruslbn at gmail dot com ¶1 year ago
In order to define leap year you must considre not only that year can be divide by 4!
The correct alghoritm is:
if (year is not divisible by 4) then (it is a common year)
else if (year is not divisible by 100) then (it is a leap year)
else if (year is not divisible by 400) then (it is a common year)
else (it is a leap year)
So the code should look like this:
if($year%4 == 0 && $year%100 != 0) {
$leapYear = 1;
} elseif($year%400 == 0) {
$leapYear = 1;
} else {
$leapYear = 0;
}
arth dot inbox at gmail dot com ¶5 months ago
Looks like date('u') is not microseconds, but is positive difference from rest part.
php > echo (DateTime::createFromFormat('U.u', '-128649659.999998'))->format('Y-m-d H:i:s.u U.u');
1965-12-03 23:59:01.999998 -128649659.999998
`U.u` parsed and formatted same, but means not 1965-12-03 23:59:00.000002.
Other words correct timestamp for example above is (-128649659 + 0.999998).
Less confusing format for it is:
php > echo DateTime::createFromFormat('U\+0.u', '-128649660+0.000002')->format('Y-m-d H:i:s.u');
1965-12-03 23:59:00.000002
Is that bug or feature?
来自 https://www.php.net/manual/zh/function.date.php