PHP 7.0.14 Released

date

(PHP 4, PHP 5, PHP 7)

dateローカルの日付/時刻を書式化する

説明

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

指定された引数 timestamp を、与えられた フォーマット文字列によりフォーマットし、日付文字列を返します。 タイムスタンプが与えられない場合は、現在の時刻が使われます。 つまり timestamp はオプションであり そのデフォルト値は time() の値です。

パラメータ

format

出力される日付文字列の書式。以下のオプションを参照ください。 定義済みの定数 も用意されており、たとえば DATE_RSS はフォーマット文字列 'D, d M Y H:i:s' と同じ意味になります。

以下の文字が format パラメータ文字列として認識されます
format 文字 説明 戻り値の例
--- ---
d 日。二桁の数字(先頭にゼロがつく場合も) 01 から 31
D 曜日。3文字のテキスト形式。 Mon から Sun
j 日。先頭にゼロをつけない。 1 から 31
l (小文字の 'L') 曜日。フルスペル形式。 Sunday から Saturday
N ISO-8601 形式の、曜日の数値表現 (PHP 5.1.0 で追加)。 1(月曜日)から 7(日曜日)
S 英語形式の序数を表すサフィックス。2 文字。 st, nd, rd または thjと一緒に使用する ことができる。
w 曜日。数値。 0 (日曜)から 6 (土曜)
z 年間の通算日。数字。(ゼロから開始) 0 から 365
--- ---
W ISO-8601 月曜日に始まる年単位の週番号 (PHP 4.1.0 で追加) 例: 42 (年の第 42 週目)
--- ---
F 月。フルスペルの文字。 January から December
m 月。数字。先頭にゼロをつける。 01 から 12
M 月。3 文字形式。 Jan から Dec
n 月。数字。先頭にゼロをつけない。 1 から 12
t 指定した月の日数。 28 から 31
--- ---
L 閏年であるかどうか。 1なら閏年。0なら閏年ではない。
o ISO-8601 形式の週番号による年。これは Y ほぼ同じだが、ISO 週番号 (W)が前年あるいは翌年に属する場合はそちらの年を使うという点が異なる(PHP 5.1.0 で追加)。 例: 1999 あるいは 2003
Y 年。4 桁の数字。 例: 1999または2003
y 年。2 桁の数字。 例: 99 または 03
--- ---
a 午前または午後(小文字) am または pm
A 午前または午後(大文字) AM または PM
B Swatch インターネット時間 000 から 999
g 時。12時間単位。先頭にゼロを付けない。 1 から 12
G 時。24時間単位。先頭にゼロを付けない。 0 から 23
h 時。数字。12 時間単位。 01 から 12
H 時。数字。24 時間単位。 00 から 23
i 分。先頭にゼロをつける。 00 から 59
s 秒。先頭にゼロをつける。 00 から 59
u マイクロ秒 (PHP 5.2.2 で追加)。 date() の場合、これは常に 000000 となることに注意しましょう。というのも、 この関数が受け取るパラメータは integer 型だからです。 一方 DateTime をマイクロ秒つきで作成した場合は、 DateTime::format() はマイクロ秒にも対応しています。 例: 654321
タイムゾーン --- ---
e タイムゾーン識別子(PHP 5.1.0 で追加) 例: UTC, GMT, Atlantic/Azores
I (大文字の i) サマータイム中か否か 1ならサマータイム中。 0ならそうではない。
O グリニッジ標準時 (GMT) との時差 例: +0200
P グリニッジ標準時 (GMT) との時差。時間と分をコロンで区切った形式 (PHP 5.1.3 で追加)。 例: +02:00
T タイムゾーンの略称 例: EST, MDT ...
Z タイムゾーンのオフセット秒数。 UTC の西側のタイムゾーン用のオフセットは常に負です。そして、 UTC の東側のオフセットは常に正です。 -43200 から 50400
全ての日付/時刻 --- ---
c ISO 8601 日付 (PHP 5 で追加されました) 2004-02-12T15:19:21+00:00
r » RFC 2822 フォーマットされた日付 例: Thu, 21 Dec 2000 16:01:07 +0200
U Unix Epoch (1970 年 1 月 1 日 0 時 0 分 0 秒) からの秒数 time() も参照

フォーマット文字列中の認識されない文字は、そのまま表示されます。 Z 形式は、 gmdate() で使用した場合、常に 0 を返します。

注意:

この関数が受け付けるのは integer のタイムスタンプだけです。したがって、書式指定文字 u が有用となるのは date_create() で作成したタイムスタンプを用いて date_format() を使用した場合のみです。

timestamp

オプションのパラメータ timestamp は、 integer 型の Unix タイムスタンプです。 timestamp が指定されなかった場合のデフォルト値は、 現在の時刻です。言い換えると、デフォルトは time() の返り値となります。

返り値

日付を表す文字列を返します。 timestamp に数字以外が使用された場合は FALSE が返され、E_WARNING レベルのエラーが発生します。

エラー / 例外

すべての日付/時刻関数は、 有効なタイムゾーンが設定されていない場合に E_NOTICE を発生させます。また、システム設定のタイムゾーンあるいは環境変数 TZ を使用した場合には E_STRICT あるいは E_WARNING を発生させます。 date_default_timezone_set() も参照ください。

変更履歴

バージョン 説明
5.1.0 有効なタイムスタンプの範囲は、通常 Fri, 13 Dec 1901 20:45:54 GMT から Tue, 19 Jan 2038 03:14:07 GMT までです (これらの日付は、32 ビット符号付き整数の最小および最大値に 対応します)。 しかし、PHP 5.1 より前のバージョンでは、システム環境によっては (例: Windows) この範囲が 1970 年 1 月 1 日から 2038 年 1 月 19 日 までに制限されます。
5.1.0

タイムゾーンがおかしい場合に E_STRICTE_NOTICE が発生するようになりました。

5.1.1 PHP 5.1.1 以降、format パラメータで標準的な 日付/時刻フォーマットを指定する際に有用な 定数がいくつか追加されました。

例1 date() の例

<?php
// 使用するデフォルトのタイムゾーンを指定します。PHP 5.1 以降で使用可能です。
date_default_timezone_set('UTC');


// 結果は、たとえば Monday のようになります。
echo date("l");

// 結果は、たとえば Monday 8th of August 2005 03:12:46 PM のようになります。
echo date('l jS \of F Y h:i:s A');

// 結果は July 1, 2000 is on a Saturday となります。
echo "July 1, 2000 is on a " date("l"mktime(000712000));

/* 書式指定パラメータに、定数を使用します。 */
// 結果は、たとえば Wed, 25 Sep 2013 15:28:57 -0700 のようになります。
echo date(DATE_RFC2822);

// 結果は、たとえば 2000-07-01T00:00:00+00:00 のようになります。
echo date(DATE_ATOMmktime(000712000));
?>

前にバックスラッシュを付けてエスケープすることにより、 フォーマット文字列として認識される文字が展開されることを防止することができます。 バックスラッシュ付きの文字は既に特別なシーケンスであり、 バックスラッシュもエスケープすることが必要となる可能性があります。

例2 date() の文字をエスケープする

<?php
// Wednesday the 15th のように出力
echo date('l \t\h\e jS');
?>

date()mktime() の両方を用いて、未来または過去の日付を知ることができます。

例3 date()mktime() の例

<?php
$tomorrow  
mktime(000date("m")  , date("d")+1date("Y"));
$lastmonth mktime(000date("m")-1date("d"),   date("Y"));
$nextyear  mktime(000date("m"),   date("d"),   date("Y")+1);
?>

注意:

サマータイムがあるため、日付や月の秒数を単純にタイムスタンプに 可減算するよりもより信頼性があります。

date() フォーマットのいくつかの例を示します。 現在の実装で特別な意味がある文字や今後の PHP のバージョンで意味が 割り付けられるであろう文字については、望ましくない結果を避けるために エスケープする必要があることに注意してください。エスケープを する際には、改行文字 \n のような文字を回避するために シングルクォートを使用してください。

例4 date() のフォーマット指定

<?php
// 今日は March 10th, 2001, 5:16:18 pm であり、
// またタイムゾーンは Mountain Standard Time (MST) であるものとします

$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
$today date("Y-m-d H:i:s");                   // 2001-03-10 17:16:18 (MySQL の DATETIME フォーマット)
?>

他の言語で日付をフォーマットするためには、date() のかわりに setlocale() および strftime() 関数を使用する必要があります。

注意

注意:

日付の文字列表現からタイムスタンプを生成するには、 strtotime() が使用できるでしょう。 さらに、いくつかのデータベースは(MySQL の » UNIX_TIMESTAMP 関数の ような)日付フォーマットからタイムスタンプへの変換関数を有しています。

ヒント

PHP 5.1 以降、$_SERVER['REQUEST_TIME'] によってリクエスト開始時のタイムスタンプが取得できるようになりました。

参考

  • gmdate() - GMT/UTC の日付/時刻を書式化する
  • idate() - ローカルな時刻/日付を整数として整形する
  • getdate() - 日付/時刻情報を取得する
  • getlastmod() - 最終更新時刻を取得する
  • mktime() - 日付を Unix のタイムスタンプとして取得する
  • strftime() - ロケールの設定に基づいてローカルな日付・時間をフォーマットする
  • time() - 現在の Unix タイムスタンプを返す
  • strtotime() - 英文形式の日付を Unix タイムスタンプに変換する
  • 定義済みの定数

add a note add a note

User Contributed Notes 44 notes

up
111
Jimmy
4 years ago
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.
up
23
ivijan dot stefan at gmail dot com
1 year ago
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.
up
23
FiraSEO
3 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 .
up
6
Anonymous
10 months ago
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)
up
7
Charlie
11 months ago
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');
?>
up
13
adityabhai at gmail dot com
3 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 !
up
11
bakerj417 at gmail dot com
4 years ago
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
up
8
eduardo at digmotor dot com dot br
7 years ago
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']));
}

?>
up
4
matthew dot hotchen at worldfirst dot com
2 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.
up
4
Bas Vijfwinkel
4 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.
up
3
@PeteWilliams
6 years ago
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();

?>
up
5
ghotinet
5 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 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;
    }
}

?>
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3
Anonymous
2 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"));
}
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5
mel dot boyce at gmail dot com
10 years ago
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.
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3
Tim Connolly
4 years ago
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;
  }
?>
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3
Anonymous
8 years ago
Correct format for a MySQL DATETIME column is
<?php $mysqltime = date ("Y-m-d H:i:s", $phptime); ?>
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3
SpikeDaCruz
10 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){
 
/*
   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");
}
?>
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-1
Anonymous
2 years ago
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;
?>
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0
Just.Kevin
7 years ago
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;
}
?>
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-2
Leopietroni
4 years ago
This function will add working day to a given timestamp

<?php
function addworkinday($timestamp,$daystoadd){
    
    
$dayoftheweek = date("N",$timestamp);
    
$sum =$dayoftheweek +$daystoadd;
    
while (
$sum >= 6) {
    
    
$daystoadd=$daystoadd+1;
   
$sum=$sum-1;
}
return
$timestamp +(60*60*24*$daystoadd);

}
?>
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-2
Edward Rudd
7 years ago
To actually make use ot the "u" (microsecond) you need to use the DateTime object and not the date() function.

For example

<?php
$t
= microtime(true);
$micro = sprintf("%06d",($t - floor($t)) * 1000000);
$d = new DateTime( date('Y-m-d H:i:s.'.$micro,$t) );

print
$d->format("Y-m-d H:i:s.u");
?>
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-1
tkachenko_ivan at bk dot ru
1 year ago
<?php
/**
* Convert a strftime format to a date format
*
* Unsupported strftime formats : %U, %W, %C, %g, %r, %R, %T, %X, %c, %D, %F, %x
* Unsupported date formats : S, n, t, L, B, G, u, e, I, P, Z, c, r
*
* @param string $strftimeFormat a strftime format
* @return string
*/
function strftimeFormatToDate($strftimeFormat) {

   
$caracs = array(
       
"%d" => "d",
       
"%a" => "D",
       
"%e" => "j",
       
"%A" => "l",
       
"%u" => "N",
       
"%w" => "w",
       
"%j" => "z",
       
"%V" => "W",
       
"%B" => "F",
       
"%m" => "m",
       
"%b" => "M",
       
"%G" => "o",
       
"%Y" => "Y",
       
"%y" => "y",
       
"%P" => "a",
       
"%p" => "A",
       
"%l" => "g",
       
"%I" => "h",
       
"%H" => "H",
       
"%M" => "i",
       
"%S" => "s",
       
"%z" => "O",
       
"%Z" => "T",
       
"%s" => "U",
    );
    return
strtr((string)$strftimeFormat, $caracs);
}

$strftimeFormat = '%Y-%m-%d %H:%M:%S';
$formatDate = strftimeFormatToDate($strftimeFormat); // Y-m-d H:i:s
?>
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-3
Chris
4 years ago
Use this to convert the local/UTC hour to the UTC/local hour:

<?php
for($utc_to_local = array(), $offset = date('Z'), $h = 0; $h < 24; $utc_to_local[] = date('G', mktime($h++)+$offset));
$local_to_utc = array_flip($utc_to_local);

echo
"2 am local is ", $local_to_utc[2], " UTC";
echo
"3 pm UTC is ", $utc_to_local[15], " local";
?>

This is useful when you need to do many conversions. Lookup tables are faster than calling date() and mktime() multiple times.
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-4
gerben at gerbenwijnja dot nl
4 years ago
I use the function below to calculate the Unix timestamp of the start of a week. It includes a boolean flag to request a GMT offset instead of the current locale setting.

<?php

function getWeekOffsetTimestamp($year, $week, $useGmt = false) {
        if (
$useGmt) {
               
// Backup timezone and set to GMT
               
$timezoneSettingBackup = date_default_timezone_get();
               
date_default_timezone_set("GMT");
        }

       
// According to ISO-8601, January 4th is always in week 1
       
$halfwayTheWeek = strtotime($year."0104 +".($week - 1)." weeks");

       
// Subtract days to Monday
       
$dayOfTheWeek = date("N", $halfwayTheWeek);
       
$daysToSubtract = $dayOfTheWeek - 1;

       
// Calculate the week's timestamp
       
$unixTimestamp = strtotime("-$daysToSubtract day", $halfwayTheWeek);

        if (
$useGmt) {
               
// Reset timezone to backup
               
date_default_timezone_set($timezoneSettingBackup);
        }

        return
$unixTimestamp;
}

?>
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-4
ttt_joe_08
2 years ago
Just FYI, it's more appropriate to say "UTC", not "GMT". GMT was given up in 1972 and UTC is now the proper way. The reason being G stands for Greenwich, which naturally upset some people.
up
-5
frank at interactinet dot com
4 years ago
If you want to compare this week with the same week last year, here is some code to get you the time at the beginning of the week.  You can then add days, hours, etc to get to the day of the week that you want to know about.

<?php
        $time_passed
= (date('N')-1)* 24 * 3600; // time since start of week in days
       
$startOfWeek = mktime(0,0,0,date('m'),date('d'),date('Y')) - $time_passed;
       
   
       
$lastyear = $startOfWeek - 365*24*3600;   

       
// make sure time used from last year is the same week of the year   
       
$weekdiff = date('W') - date('W',$lastyear);
        if(
$weekdiff != 0)
        {
           
$lastyear = $lastyear + ($weekdiff*7*24*3600);
        }
       
       
$lastyear_time_passed = (date('N',$lastyear)-1) * 24 * 3600; // time since start of week in days
       
       
$startOfWeek_lastyear = mktime(0,0,0,date('m',$lastyear),date('d',$lastyear),date('Y',$lastyear)) - $lastyear_time_passed;
?>

So now you have the unix time for the start of this week ($startOfWeek), and the start of the same week last year ($startOfWeek_lastyear).

You can convert back to datetime format easily:

<?php
       
echo date('Y-m-d H:i:s',$startOfWeek).'<br>';
        echo
date('Y-m-d H:i:s',$startOfWeek_lastyear).'<br><br>';
       
        echo
date('l F jS, Y',$startOfWeek).'<br>';
        echo
date('l F jS, Y',$startOfWeek_lastyear);
?>
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-6
lb at bostontech dot net
7 years ago
Not sure why this got ignored the first time, but this is an even simpler way to check leap year:

<?php
function isLeapYear($year)
    { return (((
$year%4==0) && ($year%100)) || $year%400==0) ? (true):(false); }
?>
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-10
webmaster1989 at gmail dot com
4 years ago
Sometimes it is very useful to convert a sql timestamp to an also called NTP time. This is often used as time date notation in XML RSS pages. To convert a timestamp to this NTP notation try the following:

<?php
 
echo date('D, d M Y h:i:s O', strtotime ($timestamp);
?>
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-3
geoffrey dot hoffman at gmail dot com
10 months ago
I just wanted to emphasise that the return value of date( ) is a string, even when the result of your date format string is a number, such as "j" -> a number 1 to 31, or 'N' -> a day number 1 for Monday through 7 for Sunday... it's still returned as a string! "1" or "7" or "31". This is much more obvious on the "zero-padded" results, but it's worth repeating.

If you aren't careful, you can get stuck in a while loop comparing days of the week with something like:

<?php
 
// Evil! Don't use this! This will never return!
  
while ( date('N', $time ) !== 7 ) {
       
$time = $time - 86400;
   }
?>

... for example. The result of date( ) should be cast to an int for numeric comparison with the exact equality operator:

<?php
 
// Works!
  
while ( (int)date('N', $time ) !== 7 ) {
       
$time = $time - 86400;
   }
?>

Wasted an hour today on that silly mistake.
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-4
akshayinbox at gmail dot com
1 year ago
When using date(), be sure to "double-escape" certain characters, for example, if printing the word "at", double escape "t" otherwise it will be treated as "tab" simply leading to a space being inserted.

Example:
<?php echo "Last updated ".date("M j<\s\u\p>S</\s\u\p\>, Y \a\\t h:i A"); ?>

will output
Last updated Aug 23rd 2015 at 2:47 PM

(assuming today is Aug 23rd 2015 and it is 2:47 PM)
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-7
scott at keenot dot es
3 years ago
If anyone needs a really fast function for converting a datetime string (i.e. as retrieved from a MySQL DATETIME entry) into a human-friendly time output analogous to date($format, $time), here's a useful function.

<?php
function fdate($datetimestring = '1970-01-01 00:00:00', $format = 'U') {
 
// Create a datetime object, return it formatted
  // If you want to give credit for this somewhere, thanks.
  // You really don't have to though; this is kinda obvious
 
$dt = new DateTime($datetimestring);
  return
$dt->format($format);
}
?>

The main purpose of this is to reduce lines of code and allow inline coding. For example:
<?php
/* ... */
echo "This page was submitted on ".fdate($row['created'], 'F j, Y g:i:s A')." and last modified ".fdate($row['modified'], 'F j, Y g:i:s A')."<br />\n";
/* ... */
?>
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-11
nathan
4 years ago
<?php
/* the following variables are set to appropriate
  characters recognized by php version 5 that
  will get the date. To display the date, we have
  to use 'echo' or 'print' to send the variable
  data to the browser
*/

$day=date("l");
$date=date("j");
$suffix=date("S");
$month=date("F");
$year=date("Y");
echo
$day . ", " . $month . " " . $date . $suffix . ", " . $year;
?>

rudimentary, simple way to due things, but it gets the job done for someone learning more on the subject.
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-14
Anonymous
4 years ago
To find last sunday for given date

<?php
         $day
= '2012-10-04';
         echo
'last sunday :  '.date("Y-m-d",strtotime($day." last Sunday "));
?>

output:

last sunday : 2012-09-30
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-12
Anon
4 years ago
I needed to convet a duration timestamp into H:i:s but whenever I did it kept bringing 5 back as 01:00:05 (due to some DST stuff) so I made this function to replace date(). It has no optimisations but hopefully someone might find it useful:

<?php
   
function get_time_string(){
       
$time = 3600+(60*32)+(50); // 01:32:50
       
$time_string = '';

       
$hours = (int)($time/(60*60));
        if(
strlen($hours) > 1){
           
$time_string = $hours.':';
        }else{
           
$time_string = '0'.$hours.':';
        }

       
$minutes = (int)(($time%(60*60))/(60));
        if(
$minutes >= 1){
            if(
strlen($minutes) > 1){
               
$time_string .= $minutes.':';
            }else{
               
$time_string .= '0'.$minutes.':';
            }

           
$seconds = ($time%(60*60))%(60);
            if(
strlen($seconds) > 1){
               
$time_string .= $seconds;
            }else{
               
$time_string .= '0'.$seconds;
            }
        }else{
            if(
strlen($time) > 1){
               
$time_string .= '00:'.$time;
            }else{
               
$time_string .= '00:0'.$time;
            }
        }
        return
$time_string;
    }
?>
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-8
stokestack at gmail dot com
4 years ago
If you want to find your server's timezone offset from GMT, it seems as though you could just do:

date('Z')

to get the number of seconds offset. But PHP requires that you call date_default_timezone_set().  So if you have to hard-code a timezone, why not simply hard-code a variable that tells you the offset from GMT?  If you set the timezone to GMT, the dates in your database will still be in local time, but time('Z') will return zero.

To keep your code portable across servers in different timezones, you can do this:

date_default_timezone_set(date_default_timezone_get())

This keeps PHP from complaining that you haven't called date_default_timezone_set(), but makes your code portable.  Ridiculous.
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-7
david dot leon at gmx dot com
2 years ago
<?php
//date returns microseconds.
function mdate($format, $microtime = null) {
       
$microtime = explode(' ', ($microtime ? $microtime : microtime()));
        if (
count($microtime) != 2) return false;
       
$microtime[0] = $microtime[0] * 1000000;
       
$format = str_replace('u', $microtime[0], $format);
        return
date($format, $microtime[1]);
    }
?>

echo mdate('Y-m-d H:i:s.u');

2014-05-19 12:41:59.202303
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-14
jc
8 years ago
date("W") returns the iso8601 week number, while date("Y") returns the _current_ year. This can lead to odd results. For example today (dec 31, 2007) it returns 1 for the week and of course 2007 for the year. This is not wrong in a strict sense because iso defines this week as the first of 2008 while we still have 2007.

So, if you don't have another way to safely retrieve the year according to the iso8061 week-date - strftime("%G") doesn't work on some systems -, you should be careful when working with date("W").

For most cases strftime("%W") should be a safe replacement.

[edit: Much easier is to use "o" (lower case O) instead of "Y"]
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-5
sanket at webvice dot co dot uk
1 year ago
<?
/**
     * This function gives you the next working days based on the buffer
     *
     * @param $date must be in YYYY-MM-DD format
     * @param int $buffer
     * @param string $holidays - You can pass either an array of holidays in YYYYYMMDD format or a URL for a .ics file
     * containing holidays this defaults to the UK govt holiday data for England and Wales
     * @return string
     */
   
    function getWorkingDays($date,$buffer=1,$holidays='') {
        if ($holidays==='') $holidays = 'https://www.gov.uk/bank-holidays/england-and-wales.ics';

        if (!is_array($holidays)) {
            $ch = curl_init($holidays);
            curl_setopt($ch,CURLOPT_RETURNTRANSFER,true);
            $ics = curl_exec($ch);
            curl_close($ch);
            $ics = explode("\n",$ics);
            $ics = preg_grep('/^DTSTART;/',$ics);
            $holidays = preg_replace('/^DTSTART;VALUE=DATE:(\\d{4})(\\d{2})(\\d{2}).*/s','$1-$2-$3',$ics);
        }

        $addDay = 0;
        while ($buffer--) {
            while (true) {
                $addDay++;
                $newDate = date('Y-m-d', strtotime("$date +$addDay Days"));
                $newDayOfWeek = date('w', strtotime($newDate));
                if ( $newDayOfWeek>0 && $newDayOfWeek<6 && !in_array($newDate,$holidays)) break;
            }
        }

        return $newDate;
    }

    ?>
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-1
david dot thomas at elliott-thomas dot com dot au
2 months 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
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-15
blinov vyacheslav AT gmail.com
5 years ago
It was oblivious and discouraging that it dont mentioned in docs. If you will use W to get week number be aware:
first days of year can be in a week of previous year, and week number always has leading zero

<?php

echo date("YW", strtotime("2011-01-07")); // gives 201101
echo date("YW", strtotime("2011-01-01")); // gives 201152
echo date("YW", strtotime("2011-12-31")); // gives 201152 too

?>

so you can`t rely on number of week given from this function inside your program if you want to use it for some logic
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-10
jock
2 years ago
As of PHP 5.3.3, date('c') will produce a string like this:

2014-06-17T16:22:42+02:00

Instead date (DATE_ISO8601) will produce:

2014-06-17T16:23:36+0200

which lacks the semicolon in the timezone part. Both are ISO8601 compliant anyway, but I found that the latter has better compatibility with other languages like python.
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-6
krejci dot info at seznam dot cz
1 year ago
I recommend to use "/" instead of "-" when creating dates:

<?
    if( date( 'd/m' ) >= date_create( '01/09' ) ) { }
?>
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-3
Al Roker
6 months ago
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();
?>
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-2
aalaap at gmail dot com
3 months ago
If you need to programatically get a list of all the supported date format identifiers, you can use this simple function:

<?php

function getDateFormat() {
    return
str_split('dDjlNSwzWFmMntLoYyaABgGhHisueIOPTZcrU');
}

?>

PHP doesn't have a built-in identifier listing function, but it has one for listing timezone names.
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