Ayuda...
Tengo una fecha asignada con la function date("w"), y exactamente a las 5 pm la fecha cambia al siguiente dia. Ej
date("w") - Lunes
y a las 5pm del Lunes cambia a Martes.
Que puede estar pasando
(PHP 4, PHP 5, PHP 7)
date — 格式化一个本地时间／日期
$format
[, int $timestamp
] )
返回将整数 timestamp
按照给定的格式字串而产生的字符串。如果没有给出时间戳则使用本地当前时间。换句话说，timestamp
是可选的，默认值为 time()。
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。
自 PHP 5.1 起在 $_SERVER['REQUEST_TIME'] 中保存了发起该请求时刻的时间戳。
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）。
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()。
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 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。
在每 次调用日期/时间函数时，如果时区无效则会引发 E_NOTICE 错误，如果使用系统设定值或 TZ
环境变量，则会引发 E_STRICT 或 E_WARNING 消息。参见
date_default_timezone_set()。
| 版本 | 说明 |
|---|---|
| 5.1.0 | 时间戳的有效取值范围为 GMT 时间的 1901 年 12 月 13 日至 GMT 时间的 2038 年 1 月 19 日。 （32 位有符号整数的取值范围）。 但是，在 PHP 5.1.0 之前的版本，在某些系统（例如 Windows）上有效取值范围为 1970 年 1 月 1 日至 2038 年 1 月 19 日。 |
| 5.1.0 |
现在发布 |
| 5.1.1 |
format 参数标准的可用日期/时间格式常量见： 常量
|
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。
Note:
使用 strtotime() 函数将一个字符串表达的日期时间转换为时间戳。 另外，一些数据库产品也提供了将日期时间格式转换为时间戳的函数。 （例如 MySQL 中的 » UNIX_TIMESTAMP 函数）。
从 PHP 5.1 版本开始，请求的开始时间可以从变量 $_SERVER['REQUEST_TIME'] 中获取。
Ayuda...
Tengo una fecha asignada con la function date("w"), y exactamente a las 5 pm la fecha cambia al siguiente dia. Ej
date("w") - Lunes
y a las 5pm del Lunes cambia a Martes.
Que puede estar pasando
I am glad and wonder about the topic creation. I am visiting this page from a long time ago. This is totally perspective clear ideas. This is sure that the information you shared is clearly identive and fabulous for keeping it in minds. http://crackswar.com/audacity-pro-crack/
I am glad and wonder about the topic creation. I am visiting this page from a long time ago. This is totally perspective clear ideas. This is sure that the information you shared is clearly identive and fabulous for keeping it in minds. http://crackswar.com/audacity-pro-crack/
Since PHP 5.6.23 en 7.0.8 the support for requesting the weeknumber for a given date, where the first day of the week is Sunday, has been removed.
For those of us still needing it, here is simple hack to get the job done.
private function getWeeknumberSundayFirstDayOfWeek(\DateTimeInterface $date)
{
if ($date->format('w') === 0) // Sunday
return (int)$date->format('W') - 1;
return (int)$date->format('W');
}
If you see the number 86400 in a date calculation, think very hard before deciding that it is correct. Not all days have 86,400 seconds in them. In many places, some days have only 82,800 seconds and some have 90,000. Occasionally, there are even fewer or even more.
Assuming that now plus 86,400 seconds is equivalent to some time tomorrow can sometimes be wrong. It might actually be the day after tomorrow or still today.
It's called Daylight Saving.
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.
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
When using 'U' to return a UNIX time stamp, you may not get what you expect. In the following example, we try to get the current Unix time stamp for a user in a different timezone.
<?php
// Doesn't work
$timezone = new \DateTimeZone($userTimeZone);
$date = new \DateTime('@' . time(), $timezone);
$date->setTimezone($timezone);
$now = $date->format('U');
?>
$now will return the same (the server's current) Unix time stamp regardless which timezone your user is in.
To get the actual Unix time stamp based on a time zone, replace format('U') as in the following example;
<?php
// This works
$timezone = new \DateTimeZone($userTimeZone);
$date = new \DateTime('@' . time(), $timezone);
$date->setTimezone($timezone);
$now = $date->getTimestamp() + $date->getOffset();
?>
If timestamp is a string, date converts it to an integer in a possibly unexpected way:
<?php
echo (int)'0x10'; //0
echo intval('0x10'); //0
echo date('s', '0x10'); //gives 16
//however, no octal conversion:
echo date('s', '010'); //gives 10
?>
(PHP 5.6.16)
For HTML5 datetime-local HTML input controls (http://www.w3.org/TR/html-markup/input.datetime-local.html) use format example: 1996-12-19T16:39:57
To generate this, escape the 'T', as shown below:
<?php
date('Y-m-d\TH:i:s');
?>
If you have a problem with the different time zone, this is the solution for that.
<?php
// first line of PHP
$defaultTimeZone='UTC';
if(date_default_timezone_get()!=$defaultTimeZone)) date_default_timezone_set($defaultTimeZone);
// somewhere in the code
function _date($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')) + $offset);
}
/* Example */
echo 'System Date/Time: '.date("Y-m-d | h:i:sa").'<br>';
echo 'New York Date/Time: '._date("Y-m-d | h:i:sa", false, 'America/New_York').'<br>';
echo 'Belgrade Date/Time: '._date("Y-m-d | h:i:sa", false, 'Europe/Belgrade').'<br>';
echo 'Belgrade Date/Time: '._date("Y-m-d | h:i:sa", 514640700, 'Europe/Belgrade').'<br>';
?>
This is the best and fastest solution for this problem. Working almost identical to date() function only as a supplement has the time zone option.
It's common for us to overthink the complexity of date/time calculations and underthink the power and flexibility of PHP's built-in functions. Consider http://php.net/manual/en/function.date.php#108613
<?php
function get_time_string($seconds)
{
return date('H:i:s', strtotime("2000-01-01 + $seconds SECONDS"));
}
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.
To quickly convert date("N") to a 0 based index with Sunday being represented as 0, you can run it against modulus 7:
<?php
$first_of_month_index = date('N', strtotime('4/1/1990')) % 7;
?>
For Microseconds, we can get by following:
echo date('Ymd His'.substr((string)microtime(), 1, 8).' e');
Thought, it might be useful to someone !
this how you make an HTML5 <time> tag correctly
<?php
echo '<time datetime="'.date('c').'">'.date('Y - m - d').'</time>';
?>
in the "datetime" attribute you should put a machine-readable value which represent time , the best value is a full time/date with ISO 8601 ( date('c') ) ,,, the attr will be hidden from users
and it doesn't really matter what you put as a shown value to the user,, any date/time format is okay !
This is very good for SEO especially search engines like Google .
Here's my solution for looking up the month number by name (used when parsing an 'ls'):
<?php
for($m=1;$m<=12;$m++){
$month=date("M",mktime(0,0,0,$m,1,2000));
$mon["$month"]=$m;
}
?>
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.
If you are having an issue getting u to work so is everyone else. The solution that I am using which I found on another site(so not taking credit) is to use this:
date("Y/m/d H:i:s"). substr((string)microtime(), 1, 6);
that will give you:
yyyy/mm/dd hh:ii:ss.uuuuuu
hope this helps someone in need!
thanks all
Things to be aware of when using week numbers with years.
<?php
echo date("YW", strtotime("2011-01-07")); // gives 201101
echo date("YW", strtotime("2011-12-31")); // gives 201152
echo date("YW", strtotime("2011-01-01")); // gives 201152 too
?>
BUT
<?php
echo date("oW", strtotime("2011-01-07")); // gives 201101
echo date("oW", strtotime("2011-12-31")); // gives 201152
echo date("oW", strtotime("2011-01-01")); // gives 201052 (Year is different than previous example)
?>
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.
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, $holidays = array()) {
// If the start and end dates are given in the wrong order, flip them.
if ($s > $e)
return networkdays($e, $s, $holidays);
// Find the ISO-8601 day of the week for the two dates.
$sd = date("N", $s);
$ed = date("N", $e);
// Find the number of weeks between the dates.
$w = floor(($e - $s)/(86400*7)); # Divide the difference in the two times by seven days to get the number of weeks.
if ($ed >= $sd) { $w--; } # If the end date falls on the same day of the week or a later day of the week than the start date, subtract a week.
// Calculate net working days.
$nwd = max(6 - $sd, 0); # If the start day is Saturday or Sunday, add zero, otherewise add six minus the weekday number.
$nwd += min($ed, 5); # If the end day is Saturday or Sunday, add five, otherwise add the weekday number.
$nwd += $w * 5; # Add five days for each week in between.
// Iterate through the array of holidays. For each holiday between the start and end dates that isn't a Saturday or a Sunday, remove one day.
foreach ($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");
// Add as many holidays as desired.
$holidays = array();
$holidays[] = "4 July 2010"; // Falls on a Sunday; doesn't affect count
$holidays[] = "6 September 2010"; // Falls on a Monday; reduces count by one
echo networkdays($start, $end, $holidays); // Returns 246
?>
Or, if you just want to know how many work days there are in any given year, here's a quick function for that one:
<?php
function workdaysinyear($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;
}
}
?>
If you want to use HTML5's <date> tag, the following code will generate the machine-readable value for the 'datetime' attribute:
<?php
/**
* formats the date passed into format required by 'datetime' attribute of <date> tag
* if no intDate supplied, uses current date.
* @param intDate integer optional
* @return string
**/
function getDateTimeValue( $intDate = null ) {
$strFormat = 'Y-m-d\TH:i:s.uP';
$strDate = $intDate ? date( $strFormat, $intDate ) : date( $strFormat ) ;
return $strDate;
}
echo getDateTimeValue();
?>
In order to determine if a year is a leap year an earlier poster suggested simply checking to see if the year is a multiple of four:
<?php
function is_leapyear_broken($year = 2004) {
return ($year%4)==0;
}
?>
While this will work for the majority of years it will not work on years that are multiples of 100 but not multiples of 400 i.e.(2100).
A function not using php's date() function that will also account for this small anomaly in leap years:
<?php
function is_leapyear_working($year = 2004) {
if((($year%4==0) && ($year%100!=0)) || $year%400==0) {
return true;
}
return false;
}
?>
While is_leapyear_working will not return true for the few non-leap years divisible by four I couldn't tell you if this is more or less efficient than using php's date() as an even earlier poster suggested:
<?php
function is_leapyear($year = 2004) {
$is_leap = date('L', strtotime("$year-1-1"));
return $is_leap;
}
?>
Thanks to tcasparr at gmail dot com for the great idea (at least for me) ;)
I changed the code a little to replicate the functionality of date_parse_from_format, once I don't have PHP 5.3.0 yet. This might be useful for someone. Hope you don't mind changing your code tcasparr at gmail dot com.
<?php
/*******************************************************
* Simple function to take in a date format and return array of associated
* formats for each date element
*
* @return array
* @param string $strFormat
*
* Example: Y/m/d g:i:s becomes
* Array
* (
* [year] => Y
* [month] => m
* [day] => d
* [hour] => g
* [minute] => i
* [second] => s
* )
*
* This function is needed for PHP < 5.3.0
********************************************************/
function dateParseFromFormat($stFormat, $stData)
{
$aDataRet = array();
$aPieces = split('[:/.\ \-]', $stFormat);
$aDatePart = split('[:/.\ \-]', $stData);
foreach($aPieces as $key=>$chPiece)
{
switch ($chPiece)
{
case 'd':
case 'j':
$aDataRet['day'] = $aDatePart[$key];
break;
case 'F':
case 'M':
case 'm':
case 'n':
$aDataRet['month'] = $aDatePart[$key];
break;
case 'o':
case 'Y':
case 'y':
$aDataRet['year'] = $aDatePart[$key];
break;
case 'g':
case 'G':
case 'h':
case 'H':
$aDataRet['hour'] = $aDatePart[$key];
break;
case 'i':
$aDataRet['minute'] = $aDatePart[$key];
break;
case 's':
$aDataRet['second'] = $aDatePart[$key];
break;
}
}
return $aDataRet;
}
?>
Also, if you need to change the format of dates:
<?php
function changeDateFormat($stDate,$stFormatFrom,$stFormatTo)
{
// When PHP 5.3.0 becomes available to me
//$date = date_parse_from_format($stFormatFrom,$stDate);
//For now I use the function above
$date = dateParseFromFormat($stFormatFrom,$stDate);
return date($stFormatTo,mktime($date['hour'],
$date['minute'],
$date['second'],
$date['month'],
$date['day'],
$date['year']));
}
?>
Correct format for a MySQL DATETIME column is
<?php $mysqltime = date ("Y-m-d H:i:s", $phptime); ?>
I've been flicking through the comments looking for some succinct date code and have noticed an alarming number of questions and over-burdened examples related to date mathematics. One of the most useful skills you can utilize when performing date math is taking full advantage of the UNIX timestamp. The UNIX timestamp was built for this kind of work.
An example of this relates to a comment made by james at bandit-dot-co-dot-en-zed. James was looking for a way to calculate the number of days which have passed since a certain date. Rather than using mktime() and a loop, James can subtract the current timestamp from the timestamp of the date in question and divide that by the number of seconds in a day:
<?php
$days = floor((time() - strtotime("01-Jan-2006"))/86400);
print("$days days have passed.\n");
?>
Another usage could find itself in a class submitted by Kyle M Hall which aids in the creation of timestamps from the recent past for use with MySQL. Rather than the looping and fine tuning of a date, Kyle can use the raw UNIX timestamps (this is untested code):
<?php
$ago = 14; // days
$timestamp = time() - ($ago * 86400);
?>
Hopefully these two examples of "UNIX-style" timestamp usage will help those finding date mathematics more elusive than it should be.
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){
/*
Takes any Gregorian date and returns the Gregorian
date of Orthodox Easter for that year.
*/
$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;
//Orthodox Easter for this year will fall $rc days after April 3
return strtotime("3 April $year + $rc days");
}
?>