date

(PHP 4, PHP 5)

dateYerel tarihi/saati biçimlendirir

Açıklama

string date ( string $biçim [, int $zaman_damgası ] )

zaman_damgası değiştirgesi ile belirtilen zamanı ya da zaman damgası değiştirgesi kullanılmamışsa yerel zamanı, belirtilen biçime göre biçimlendirerek döndürür. Başka bir deyişle, zaman_damgası değiştirgesini belirtmek isteğe bağlıdır ve varsayılan değeri time() işlevinin değeridir.

Değiştirgeler

biçim

Çıktılanan zamanın string türünden biçimi. Biçimlendirme seçenekleri için aşağıya bakınız. Ayrıca burada kullanılabilecek önceden tanımlanmış çeşitli tarih sabitleri vardır. Örneğin, DATE_RSS sabiti 'D, d M Y H:i:s' biçemini içerir.

Aşağıdaki karakterler biçim değiştirge dizgesi içinde tanınır.
biçim karakteri Açıklama Örnek sonuç
Gün --- ---
d Ay günlerinin sıfır dolgulu iki haneli gösterimi 01'den 31'e
D Ay günlerinin üç harfli metinsel gösterimi Pzt'den Paz'a
j Ay günlerinin sıfır dolgusuz gösterimi 1'den 31'e
l (küçük 'L' harfi) Hafta günlerinin tam metinsel gösterimi Pazar'dan Cumartesi'ye
N Hafta günlerinin ISO-8601 standardında sayısal gösterimi (PHP 5.1.0'da eklenmiştir) 1'den (Pazartesi için) 7'ye (Pazar için)
S Ay günleri için 2 karakterli İngilizce sıralama ekleri st, nd, rd ya da th. j ile uyumlu çalışmaktadır.
w Hafta günlerinin sayısal gösterimi 0'dan (Pazar için) 6'ya (Cumartesi için)
z Yılın günleri (0'dan başlar) 0'dan 365'e
Hafta --- ---
W ISO-8601 standartına göre yılın hafta numarası, hafta başlangıcı Pazartesi'dir (PHP 4.1.0 sürümüyle eklenmiştir) Örneğin: 42 (Yılın 42'inci haftası)
Ay --- ---
F Ayın tam metinsel gösterimi, Ocak ya da Mart gibi January'den December'a
m Ayın sıfır dolgulu sayısal gösterimi 01'den 12'ye
M Ayın üç karakterli, metinsel kısa gösterimi Jan'dan Dec'e kadar
n Ayın sıfır dolgusuz sayısal gösterimi 1'den 12'ye kadar
t Belirtilen ayın gün sayısı 28'den 31'e
Yıl --- ---
L Artık yıl olduğunda Eğer artık yılsa 1, değilse 0.
o ISO-8601 standardı yıl numarası. ISO hafta numaralarının (W) ait olduğu yılın gösterilmesi dışında Y ile aynı değere sahiptir. (PHP 5.1.0 sürümünde eklenmiştir) Örnekler: 1999 ya da 2003 gibi
Y Yılın 4 haneli sayısal, tam gösterimi Örnekler: 1999 ya da 2003 gibi
y Yılın iki haneli gösterimi Örnekler: 99 ya da 03 gibi
Saat --- ---
a Küçük harfli öğleden önce ve öğleden sonra am ya da pm
A Büyük harfli öğleden önce ve öğleden sonra AM ya da PM
B Swatch İnternet saati 000'dan 999'a
g Saatin, 12-saatlik sıfır dolgusuz gösterimi 1'den 12'ye
G Saatin, 24-saatlik sıfır dolgusuz gösterimi 0'dan 23'e
h Saatin, 12-saatlik sıfır dolgulu gösterimi 01'den 12'ye
H Saatin, 24-saatlik sıfır dolgulu gösterimi 00'dan 23'e
i Sıfır dolgulu dakika gösterimi 00 ile 59 arasında
s Sıfır dolgulu saniye gösterimi 00 ile 59 arasında
u Mikrosaniye (PHP 5.2.2 sürümüyle eklenmiştir) Örneğin: 654321
Zaman dilimi --- ---
e Zaman dilimi belirteci (PHP 5.1.0 sürümüyle eklenmiştir) Örnekler: UTC, GMT, Europe/Istanbul
I (büyük ı) Yaz saati uygulaması var mı? Varsa 1, yoksa 0.
O Saat olarak Greenwich zamanı (GMT) farkı Örneğin: +0200
P Saat ve dakika olarak Greenwich zamanı (GMT) farkı (PHP 5.1.3 sürümüyle eklenmiştir) Örneğin: +02:00
T Zaman dilimi kısaltması Örnekler: EST, EET gibi
Z Saniye cinsinden saat farkı. UTC'nin batısı daima negatif, doğusu ise daima pozitif değerlidir. -43200'den 50400'e
Tam Tarih/Saat --- ---
c ISO 8601 standardı tarih (PHP 5'te' eklenmiştir) 2004-02-12T15:19:21+00:00
r » RFC 2822 biçiminde tarih Örneğin: Thu, 21 Dec 2000 16:01:07 +0200
U Unix Zaman Başlangıcından (1 Ocak 1970 00:00:00 GMT) itibaren geçen saniye sayısı time() işlevine bakınız

Biçim dizgesinde tanınmayan karakterler olduğu gibi yazdırılacaktır. Z biçimi gmdate() işleviyle kullanıldığında daima 0 değerini döndürür.

Bilginize:

Bu işlev sadece integer türünde zaman damgalarını kabul etmektedir. u biçim karakteri sadece date_format() işlevinde, date_create() işleviyle kullanıcı tabanlı bir zaman damgası oluşturulduğunda kullanılabilir.

zaman_damgası

Seçimlik zaman_damgası değiştirgesi integer türünde bir Unix zaman damgası olup belirtilmediği takdirde yerel zaman kullanılır. Başka bir deyişle, time() işlevinden dönen değer öntanımlıdır.

Dönen Değerler

Biçimlendirilmiş tarih dizgesi döndürür. Eğer zaman_damgası değiştirgesi için sayı olmayan bir değer girilirse; FALSE döndürülür ve E_WARNING seviyesinde bir hata çıktılanır.

Hatalar/İstisnalar

Bir tarih/zaman işlevine yapılan her çağrı eğer zaman dilimi ayarı geçerli değilse bir E_NOTICE üretir. Ve/veya eğer sistem ayarları veya TZ ortam değişkeni kullanılıyorsa bir E_STRICT veya bir E_WARNING iletisi üretir. Ayrıca bakınız: date_default_timezone_set()

Sürüm Bilgisi

Sürüm: Açıklama
5.1.0 Zaman damgasının geçerlilik aralığı, genellikle Cum, 13 Ara 1901 20:45:54 GMT ile Per, 19 Oca 2038 03:14:07 GMT arasındadır. (Bu tarih değerleri aynı zamanda en küçük ve en büyük 32-bit işaretli tamsayıları temsil etmektedir.) Bununla birikte, PHP 5.1.0'den önce bu aralık bazı sistemlerde 01-01-1970 ile 19-01-2038 arasıyla sınırlıydı. (ör: Windows).
5.1.0

Zaman dilimi hatalarında artık E_STRICT ve E_NOTICE çıktılanıyor.

5.1.1 Standart tarih/zaman biçimleri için, biçim değiştirgesinde kullanılabilecek yararlı sabitler devreye girdi.

Örnekler

Örnek 1 - date() örnekleri

<?php
// varsayılan zaman dilimini ayarla. PHP 5.1'den beri kullanılabilir.
date_default_timezone_set('UTC');


// Şöyle bir şey basar: Monday
echo date("l");

// Şöyle bir şey basar: Monday 8th of August 2005 03:12:46 PM
echo date('l jS \of F Y h:i:s A');

// Şöyle bir şey basar: July 1, 2000 is on a Saturday
echo "July 1, 2000 is on a " date("l"mktime(000712000));

/* biçim değiştirgesi için sabit kullanımı*/
// Şöyle bir şey basar: Mon, 15 Aug 2005 15:12:46 UTC
echo date(DATE_RFC822);

// Şöyle bir şey basar: 2000-07-01T00:00:00+00:00
echo date(DATE_ATOMmktime(000712000));
?>

Biçim dizgesinin içinde tanınan bir karakterin önüne bir tersbölü imi koyarak yorumlanmasını engelleyebilirsiniz. Eğer tersbölülü karakter zaten özel bir dizilimi ifade ediyorsa, bir tane daha tersbölü karakterine ihtiyacınız olacaktır.

Örnek 2 - date() işlevinde önceleme karakterleri

<?php
// Şöyle bir şey basar: Wednesday the 15th
echo date("l \\t\h\e jS");
?>

date() ve mktime() işlevleri birlikte, geçmiş ya da gelecek zamanın bulunmasında kullanılabilir.

Örnek 3 - date() ve mktime() örneği

<?php
$yarın  
mktime(000date("m")  , date("d")+1date("Y"));
$geçenay mktime(000date("m")-1date("d"),   date("Y"));
$gelecekyıl mktime(000date("m"),   date("d"),   date("Y")+1);
?>

Bilginize:

Bu kullanım, yaz saati uygulamasından dolayı, bir zaman damgasına basitçe saniye, gün ve ay ekleme veya çıkartma işlemlerinden daha güvenilirdir.

Bazı date() işlevi biçimlendirme örnekleri. Diğer öncelenen karakterlerin, geçerli bir özel anlama sahip olabileceklerinden istenmeyen sonuçlara neden olacağını ve gelecekteki PHP sürümlerinde kullanılmak üzere tahsis edilebileceklerini dikkate alın. Önceleme yaparken \n gibi özel karakterlerin oluşmasını önlemek için dizgeyi tek tırnaklar arasına almayı unutmayın.

Örnek 4 - date() Biçemlemesi

<?php
// Bugünün; March 10th, 2001, 5:16:18 pm olduğunu ve
// Mountain Standard Time (MST) Zaman Diliminde olduğumuzu varsayıyoruz

$bugün date("F j, Y, g:i a");                 // March 10, 2001, 5:16 pm
$bugün date("m.d.y");                         // 03.10.01
$bugün date("j, n, Y");                       // 10, 3, 2001
$bugün date("Ymd");                           // 20010310
$bugün date('h-i-s, j-m-y, it is w Day');     // 05-16-18, 10-03-01, 1631 1618 6 Satpm01
$bugün date('\i\t \i\s \t\h\e jS \d\a\y.');   // it is the 10th day.
$bugün date("D M j G:i:s T Y");               // Sat Mar 10 17:16:18 MST 2001
$bugün date('H:m:s \m \i\s\ \m\o\n\t\h');     // 17:03:18 m is month
$bugün date("H:i:s");                         // 17:16:18
?>

Tarihi farklı dillerde biçimlendirmek için, date() işlevi yerine setlocale() ve strftime() işlevini kullanmalısınız.

Notlar

Bilginize:

Tarihin dizge gösteriminden zaman damgası üretirken, strtotime() işlevini kullanabilirsiniz. Ayrıca, bazı veritabanları girilen zaman damgalarını kendi biçimine çeviren işlevlere sahiptir (MySQL'in »  UNIX_TIMESTAMP işlevi gibi).

İpucu

PHP 5.1 sürümünden beri istek başlangıcının zaman damgası $_SERVER['REQUEST_TIME'] değişkeniyle tanımlanmaktadır.

Ayrıca Bakınız

add a note add a note

User Contributed Notes 42 notes

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60
Jimmy
3 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.
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5
Leopietroni
2 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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4
adityabhai at gmail dot com
1 year 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 !
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7
FiraSEO
1 year 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 .
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6
bakerj417 at gmail dot com
2 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
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4
Anonymous
9 months 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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4
Tim Connolly
2 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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7
SpikeDaCruz
8 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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4
nathan
2 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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2
Anonymous
1 year 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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3
webmaster1989 at gmail dot com
2 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
Edward Rudd
5 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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4
mel dot boyce at gmail dot com
8 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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1
frank at interactinet dot com
2 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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2
Anonymous
6 years ago
Correct format for a MySQL DATETIME column is
<?php $mysqltime = date ("Y-m-d H:i:s", $phptime); ?>
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2
ghotinet
4 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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1
JonathanCross.com
6 years ago
<?php
// A demonstration of the new DateTime class for those
// trying to use dates before 1970 or after 2038.
?>
<h2>PHP 2038 date bug demo (php version <?php echo phpversion(); ?>)</h1>
<div style='float:left;margin-right:3em;'>
<h3>OLD Buggy date()</h3>
<?php
  $format
='F j, Y';
  for (
$i = 1900; $i < 2050; $i++) {
   
$datep = "$i-01-01";
   
?>
    Trying: <?php echo $datep; ?> = <?php echo date($format, strtotime($datep)); ?><br>
    <?php
 
}
?></div>
<div style='float:left;'>
  <h3>NEW DateTime Class (v 5.2+)</h3><?php
 
for ( $i = 1900; $i < 2050; $i++) {
   
$datep = "$i-01-01";
   
$date = new DateTime($datep);
   
?>
    Trying: <?php echo $datep; ?> = <?php echo $date->format($format); ?><br>
    <?php
 
}
?></div>
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0
jock
6 months 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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0
david dot leon at gmx dot com
7 months 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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0
matthew dot hotchen at worldfirst dot com
10 months 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.
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0
Bas Vijfwinkel
2 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.
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0
gerben at gerbenwijnja dot nl
2 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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0
lb at bostontech dot net
5 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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0
Just.Kevin
5 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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0
jc
6 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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-1
eduardo at digmotor dot com dot br
5 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']));
}

?>
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m_ocx at yahoo dot com
2 years ago
Here is a cool Date class to implement the date function:

<?php
/*
* @author    Gchats
*
* Date class
*/
class Date
{   
    private
$shortDateFormat = "F j, Y";
    private
$longDateFormat = "F j, Y, g:i a";
    private
$timestamp = 0;
   
   
/**
    * Default constructor
    *
    * @param    integer        $timestamp    unix time stamp
    */
   
function __construct($timestamp = 0)
    {
       
$this->timestamp = $timestamp;
    }
   
   
/**
    * Returns the given timestamp in the constructor
    *
    * @return    integer        time stamp
    */
   
public function getTime()
    {
        return (int)
$this->timestamp;
    }
   
   
/*
     * Returns long formatted date of the given timestamp
     *
     * @access public
     * @return     string    Long formatted date
     */
   
public function long()
    {
        if (
$this->timestamp > 0 )
        {
            return
date ( $this->longDateFormat , $this->timestamp );
        }
        else
        {
            return
"";
        }
    }

   
/*
     * Returns short formatted date of the given timestamp
     *
     * @access public
     * @return     string    Short formatted date
     */   
   
public function short()
    {
        if (
$this->timestamp > 0 )
        {
            return
date ( $this->shortDateFormat , $this->timestamp );
        }
        else
        {
            return
"";
        }
    }
   
    public function
__toString()
    {
        return
$this->timestamp;
    }
   
}
?>
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-1
@PeteWilliams
4 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();

?>
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stokestack at gmail dot com
2 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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Anon
2 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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-3
Anonymous
1 year ago
Was trying to compare dates when I noticed that:

<?php

var_dump
(date('d.m.Y', null));//string(10) "01.01.1970"
var_dump(date('d.m.Y', ''));//bool(false)

?>

Thought it's worth mentioning. Caused some weird logs to be produced in our system since this does not evaluate to the same.
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Chris
2 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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scott at keenot dot es
1 year 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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-7
Anonymous
2 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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-2
ttt_joe_08
11 months 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.
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-5
chubby at chicks dot com
6 years ago
<?php
/**
     * Checks wether a date is between an interval
     *
     * Usage:
     *     
     * // check if today is older than 2008/12/31
     * var_dump(currentDayIsInInterval('2008/12/31'));
     * // check if today is younger than 2008/12/31
     * var_dump(currentDayIsInInterval(null,'2008/12/31'));
     * // check if today is between 2008/12/01 and 2008/12/31
     * var_dump(currentDayIsInInterval('2008/12/01','2008/12/31')); 
     *
     * Will trigger errors if date is in wrong format, notices if $begin > $end    
     *         
     * @param string $begin Date string as YYYY/mm/dd
     * @param string $end Date string as YYYY/mm/dd
     * @return bool 
     */
function currentDayIsInInterval($begin = '',$end = '')
{
       
$preg_exp = '"[0-9][0-9][0-9][0-9]/[0-9][0-9]/[0-9][0-9]"';
       
$preg_error = 'Wrong parameter passed to function '.__FUNCTION__.' : Invalide date
format. Please use YYYY/mm/dd.'
;
       
$interval_error = 'First parameter in '.__FUNCTION__.' should be smaller than
second.'
;
        if(empty(
$begin))
        {
               
$begin = 0;
        }
        else
        {
                if(
preg_match($preg_exp,$begin))
                {
                       
$begin = (int)str_replace('/','',$begin);
                }
                else
                {
                       
trigger_error($preg_error,E_USER_ERROR);
                }
        }
        if(empty(
$end))
        {
               
$end = 99999999;
        }
        else
        {
                if(
preg_match($preg_exp,$end))
                {
                       
$end = (int)str_replace('/','',$end);
                }
                else
                {
                       
trigger_error($preg_error,E_USER_ERROR);
                }
        }
        if(
$end < $begin)
        {
               
trigger_error($interval_error,E_USER_WARNING);
        }
       
$time = time();
       
$now = (int)(date('Y',$time).date('m',$time).date('j',$time));
        if(
$now > $end or $now < $begin)
        {
                return
false;
        }
        return
true;
}
?>
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lehal2 at hotmail dot com
2 years ago
here is an example how you can make numeric days of the week from 1 to 7(Monday to Friday)

<?php
$currentdate 
= mktime(0, 0, 0, date("m")  , date("d"), date("Y"));
     echo
$day_eg1 = date ('N',$currentdate);
      echo
$day_eg2 = date("N", $today+1 * 24 * 3600);
    echo
$day_eg3= date("N", $today+2 * 24 * 3600);
    echo
$day_eg4 = date("N", $today+3 * 24 * 3600);
    echo
$day_eg5 = date("N", $today+4 * 24 * 3600);
    echo
$day_eg6 = date("N", $today+5 * 24 * 3600);
    echo
$day_eg7 = date("N", $today+6 * 24 * 3600);
?>
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Jacques Marais
11 months ago
If you want to print something like: Tuesday, the 14th of January, 2014

Use this:

<?php
echo date("l", strtotime("now")).', the'.date(" jS", strtotime("now")).' of'.date(" F, Y", strtotime("now"));
?>

This is because you cannot use words in the date string. If you use words in the date string it will be seen as a format character

So if you use:

<?php
echo date("l, the jS of F, Y", strtotime("now"));
?>

It will print something like: Tuesday, 3108Europe/Berlin 14th 2014f January, 2014
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blinov vyacheslav AT gmail.com
3 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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matt
2 years ago
date() has some strange behavior at extremely high values:

<?php
echo "9223372036854775805: " . date("Y-m-d g:i:s a"9223372036854775805) . "\n";
echo
"9223372036854775806: " . date("Y-m-d g:i:s a"9223372036854775806) . "\n";
echo
"9223372036854775807: " . date("Y-m-d g:i:s a"9223372036854775807) . " (0x7FFFFFFFFFFFFFFF)\n";
echo
"9223372036854775808: " . date("Y-m-d g:i:s a"9223372036854775808) . "\n";
echo
"9223372036854775809: " . date("Y-m-d g:i:s a"9223372036854775809) . "\n";
echo
"9223372036854775810: " . date("Y-m-d g:i:s a"9223372036854775810) . "\n";
echo
"...\n";
echo
"9223372036854776832: " . date("Y-m-d g:i:s a"9223372036854776832) . "\n";
echo
"9223372036854776833: " . date("Y-m-d g:i:s a"9223372036854776833) . "\n";
echo
"...\n";
echo
"9223372036854778879: " . date("Y-m-d g:i:s a"9223372036854778879) . "\n";
echo
"9223372036854778880: " . date("Y-m-d g:i:s a"9223372036854778880) . "\n";
echo
"...\n";
echo
"9223372036854780928: " . date("Y-m-d g:i:s a"9223372036854780928) . "\n";
echo
"9223372036854780929: " . date("Y-m-d g:i:s a"9223372036854780929) . "\n";
echo
"...\n";
echo
"9223372036854782975: " . date("Y-m-d g:i:s a"9223372036854782975) . "\n";
echo
"9223372036854782976: " . date("Y-m-d g:i:s a"9223372036854782976) . "\n";
echo
"...\n";
echo
"9223372036854785024: " . date("Y-m-d g:i:s a"9223372036854785024) . "\n";
echo
"9223372036854785025: " . date("Y-m-d g:i:s a"9223372036854785025) . "\n";
echo
"...\n";
echo
"9223372036854787071: " . date("Y-m-d g:i:s a"9223372036854787071) . "\n";
echo
"9223372036854787072: " . date("Y-m-d g:i:s a"9223372036854787072) . "\n";
echo
"...\n";
echo
"9223372036854789120: " . date("Y-m-d g:i:s a"9223372036854789120) . "\n";
echo
"9223372036854789121: " . date("Y-m-d g:i:s a"9223372036854789121) . "\n";
echo
"...\n";
echo
"9223372036854791167: " . date("Y-m-d g:i:s a"9223372036854791167) . "\n";
echo
"9223372036854791168: " . date("Y-m-d g:i:s a"9223372036854791168) . "\n";
echo
"...\n";
echo
"9223372036854793215: " . date("Y-m-d g:i:s a"9223372036854793215) . "\n";
echo
"9223372036854793216: " . date("Y-m-d g:i:s a"9223372036854793216) . "\n";
echo
"9223372036854793217: " . date("Y-m-d g:i:s a"9223372036854793217) . "\n";
echo
"9223372036854793218: " . date("Y-m-d g:i:s a"9223372036854793218) . "\n";
?>

Output:

9223372036854775805: 292277026596-12-04 10:30:05 am
9223372036854775806: 292277026596-12-04 10:30:06 am
9223372036854775807: 292277026596-12-04 10:30:07 am (0x7FFFFFFFFFFFFFFF)
9223372036854775808: 292277026596-12-04 10:30:08 am
9223372036854775809: 292277026596-12-04 10:30:08 am
9223372036854775810: 292277026596-12-04 10:30:08 am
...
9223372036854778879: 292277026596-12-04 10:30:08 am
9223372036854778880: 292277026596-12-04 11:04:16 am
...
9223372036854778879: 292277026596-12-04 11:04:16 am
9223372036854778880: 292277026596-12-04 11:38:24 am
...
9223372036854780928: 292277026596-12-04 11:38:24 am
9223372036854780929: 292277026596-12-04 12:12:32 pm
...
9223372036854782975: 292277026596-12-04 12:12:32 pm
9223372036854782976: 292277026596-12-04 12:46:40 pm
...
9223372036854785024: 292277026596-12-04 12:46:40 pm
9223372036854785025: 292277026596-12-04 1:20:48 pm
...
9223372036854787071: 292277026596-12-04 1:20:48 pm
9223372036854787072: 292277026596-12-04 1:54:56 pm
...
9223372036854789120: 292277026596-12-04 1:54:56 pm
9223372036854789121: 292277026596-12-04 2:29:04 pm
...
9223372036854791167: 292277026596-12-04 2:29:04 pm
9223372036854791168: 292277026596-12-04 3:03:12 pm
...
9223372036854793215: 292277026596-12-04 3:03:12 pm
9223372036854793216: 292277026596-12-04 3:03:12 pm
9223372036854793217: -292277022657-01-27 8:37:04 am
9223372036854793218: -292277022657-01-27 8:37:04 am

---

So, the last reliable unix timecode is 9223372036854775808 (0x1000000000000000). Not that you would probably ever need a date that high.
up
-5
Ryan
2 months ago
That  is just too hard anyone have it easier terms for a lad who only has internet for 5 mis a day cause he has to walk his pet peanut
up
-5
Manu Manjunath
8 months ago
If you want to use "u" format specifier for micrseconds without changing to DateTime object, you may write a function as below:
<?php
/**
* Quick replacement to date() function to handle the 'u' format specifier (for microseconds)
* @param string $format Date format string - the same format string you would pass to date() function
* @param float $timestamp [optional] Unix timestamp with microseconds - Typically output of <b>microtime(true)</b>
* @return string Formatted string
*/
function date_with_micro($format, $timestamp = null) {
    if (
is_null($timestamp) || $timestamp === false) {
       
$timestamp = microtime(true);
    }
   
$timestamp_int = (int) floor($timestamp);
   
$microseconds = (int) round(($timestamp - floor($timestamp)) * 1000000.0, 0);
   
$format_with_micro = str_replace("u", $microseconds, $format);
    return
date($format_with_micro, $timestamp_int);
}
?>

You can safely replace your date() function with date_with_micro().
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