(PHP 4, PHP 5)
strftime — Formatiert eine Zeit-/Datumsangabe nach den lokalen Einstellungen
Gibt einen String zurück, der den angegebenen Formatierungs-Merkmalen entspricht. Dabei wird der gegebene Timestamp/ Zeitstempel oder - falls dieser fehlt - die momentane lokale Zeit benutzt. Der Monats- und Wochentagsname wird entsprechend des per setlocale() eingestellten Wertes gesetzt.
Nachfolgend die im Formatierungsstring gültigen / bekannten Platzhalter:
Sun Solaris scheint mit dem Sonntag als 1 zu starten, obwohl ISO 9889:1999 (der aktuelle C Standard) klar festlegt, dass es der Montag sein sollte.
Hinweis:
Es ist durchaus möglich, dass Ihre C-Bibliothek nicht alle angegebenen Formatierungszeichen erkennt. In diesem Fall werden diese Zeichen von der PHP-Funktion strftime() nicht unterstützt. Zusätzlich unterstützen nicht alle Plattformen negative Werte eines Timestamps, deshalb könnte der Wertebereich eines Datums durch den Beginn der Unix Epoche begrenzt sein. Das bedeutet, dass z.B. %e, %T, %R und %D (und vielleicht noch weitere) und Zeitangaben vor dem Jan 1, 1970 auf Windowssystemen, einigen Linuxdisrtibutionen und einigen anderen Betriebssytemen nicht funktionieren. Für Windowsbetriebssysteme finden Sie eine komplette Übersicht der gültigen / bekannten Platzhalter im Formatierungsstring auf dieser » MSDN Webseite.
Beispiel #1 strftime() locale Beispiel
<?php
setlocale(LC_TIME, "C");
echo strftime("%A");
setlocale(LC_TIME, "fi_FI");
echo strftime(" in Finnish is %A,");
setlocale(LC_TIME, "fr_FR");
echo strftime(" in French %A and");
setlocale(LC_TIME, "de_DE");
echo strftime(" in German %A.\n");
?>
Hinweis: %G und %V basieren auf ISO 8601:1988 Wochennummern und können unerwartete (obwohl korrekte) Ergebnisse liefern, wenn Sie das Nummernsystem nicht gründlich verstehen. Sehen Sie weiter oben bei %V nach und beachten Sie die folgenden Beispiele.
Beispiel #2 ISO 8601:1988 Wochennummer Beispiel
<?php
/* December 2002 / January 2003
ISOWk M Tu W Thu F Sa Su
----- ----------------------------
51 16 17 18 19 20 21 22
52 23 24 25 26 27 28 29
1 30 31 1 2 3 4 5
2 6 7 8 9 10 11 12
3 13 14 15 16 17 18 19 */
// Ausgabe: 12/28/2002 - %V,%G,%Y = 52,2002,2002
echo "12/28/2002 - %V,%G,%Y = " . strftime("%V,%G,%Y", strtotime("12/28/2002")) . "\n";
// Ausgabe: 12/30/2002 - %V,%G,%Y = 1,2003,2002
echo "12/30/2002 - %V,%G,%Y = " . strftime("%V,%G,%Y", strtotime("12/30/2002")) . "\n";
// Ausgabe: 1/3/2003 - %V,%G,%Y = 1,2003,2003
echo "1/3/2003 - %V,%G,%Y = " . strftime("%V,%G,%Y",strtotime("1/3/2003")) . "\n";
// Ausgabe: 1/10/2003 - %V,%G,%Y = 2,2003,2003
echo "1/10/2003 - %V,%G,%Y = " . strftime("%V,%G,%Y",strtotime("1/10/2003")) . "\n";
/* December 2004 / January 2005
ISOWk M Tu W Thu F Sa Su
----- ----------------------------
51 13 14 15 16 17 18 19
52 20 21 22 23 24 25 26
53 27 28 29 30 31 1 2
1 3 4 5 6 7 8 9
2 10 11 12 13 14 15 16 */
// Ausgabe: 12/23/2004 - %V,%G,%Y = 52,2004,2004
echo "12/23/2004 - %V,%G,%Y = " . strftime("%V,%G,%Y",strtotime("12/23/2004")) . "\n";
// Ausgabe: 12/31/2004 - %V,%G,%Y = 53,2004,2004
echo "12/31/2004 - %V,%G,%Y = " . strftime("%V,%G,%Y",strtotime("12/31/2004")) . "\n";
// Ausgabe: 1/2/2005 - %V,%G,%Y = 53,2004,2005
echo "1/2/2005 - %V,%G,%Y = " . strftime("%V,%G,%Y",strtotime("1/2/2005")) . "\n";
// Ausgabe: 1/3/2005 - %V,%G,%Y = 1,2005,2005
echo "1/3/2005 - %V,%G,%Y = " . strftime("%V,%G,%Y",strtotime("1/3/2005")) . "\n";
?>
Siehe auch setlocale(), mktime() und die » Open Group Spezifikation von strftime().
%V may fail with some systems (Windows XP, at least). Here is a function that should work to get the week number of a day (timestamped), according to ISO 8601.
"should work" as in "it is working with my understanding of this norm", where 1st of january can be week 52, 53 or 01. Hopefully.
testing (php_uname("s") == "Windows NT") or equivalent can be an option (when switching between Wampserver and a GNU server, for instance).
Please, erase and correct my message if there is any error.
<?php
function week_isonumber ($time) {
// When strftime("%V") fails, some unoptimized workaround
//
// http://en.wikipedia.org/wiki/ISO_8601 : week 1 is "the week with the year's first Thursday in it (the formal ISO definition)"
$year = strftime("%Y", $time);
$first_day = strftime("%w", mktime(0, 0, 0, 1, 1, $year));
$last_day = strftime("%w", mktime(0, 0, 0, 12, 31, $year));
$number = $isonumber = strftime("%W", $time);
// According to strftime("%W"), 1st of january is in week 1 if and only if it is a monday
if ($first_day == 1)
$isonumber--;
// 1st of january is between monday and thursday; starting (now) at 0 when it should be 1
if ($first_day >= 1 && $first_day <= 4)
$isonumber++;
else if ($number == 0)
$isonumber = week_isonumber(mktime(0, 0, 0, 12, 31, $year - 1));
if ($isonumber == 53 && ($last_day == 1 || $last_day == 2 || $last_day == 3))
$isonumber = 1;
return sprintf("%02d", $isonumber);
}
?>
Why not use utf8_encode to fix problems with letters in ISO-8859-1 and charset set to UTF-8?
For example:
<?php
setlocale(LC_TIME, "de_DE");
echo utf8_encode(strftime('%B')); // Output e.g.: März
?>
The format "%e" does not work on Windows.
There is a bug entry : http://bugs.php.net/bug.php?id=45847
It's because strftime is not portable, it use the operating system function.
For Win32, to get more documentation we have to consult the Windows "Run-Time Library Reference" for strftime :
http://msdn.microsoft.com/en-us/library/fe06s4ak%28VS.71%29.aspx
And we can find the solution:
replace "%e" by "%#d"
the "#" remove leading zeros (if any).
Cyrille
Created this small method to convert a date format to a strftime format. One format is enough to learn :)
<?php
/**
* Convert a date format to a strftime format
*
* Timezone conversion is done for unix. Windows users must exchange %z and %Z.
*
* Unsupported date formats : S, n, t, L, B, G, u, e, I, P, Z, c, r
* Unsupported strftime formats : %U, %W, %C, %g, %r, %R, %T, %X, %c, %D, %F, %x
*
* @param string $dateFormat a date format
* @return string
*/
public static function dateFormatToStrftime($dateFormat) {
$caracs = array(
// Day - no strf eq : S
'd' => '%d', 'D' => '%a', 'j' => '%e', 'l' => '%A', 'N' => '%u', 'w' => '%w', 'z' => '%j',
// Week - no date eq : %U, %W
'W' => '%V',
// Month - no strf eq : n, t
'F' => '%B', 'm' => '%m', 'M' => '%b',
// Year - no strf eq : L; no date eq : %C, %g
'o' => '%G', 'Y' => '%Y', 'y' => '%y',
// Time - no strf eq : B, G, u; no date eq : %r, %R, %T, %X
'a' => '%P', 'A' => '%p', 'g' => '%l', 'h' => '%I', 'H' => '%H', 'i' => '%M', 's' => '%S',
// Timezone - no strf eq : e, I, P, Z
'O' => '%z', 'T' => '%Z',
// Full Date / Time - no strf eq : c, r; no date eq : %c, %D, %F, %x
'U' => '%s'
);
return strtr((string)$dateFormat, $caracs);
}
?>
I use it with this condition on a date format :
if(preg_match("/(D|l|F|M)/", $format))
You can remove leading "0" from %m (two digit representation of the month) by using "-".
%-m => Month of the year (1 to 12) without leading zero
On the Linux server I'm using, strftime() also accepts a "-" option to request no padding:
<?php
$ts = strtotime("4 Nov 2009");
echo strlen(strftime("%-e", $ts)), "\n"; // "1" (no padding)
echo strlen(strftime("%e", $ts)), "\n"; // "2" (space padded)
?>
This is that worked with UTF-8 encoding on Linux server, with right accents:
<?php
setlocale(LC_ALL, 'hu_HU.UTF8');
echo(strftime('%Y. %B %d. %A'));
?>
Output is:
2009. november 02. hétfő
Also, this one can be used, if not utf-8 preferred:
<?php
setlocale(LC_ALL, 'hu_HU.ISO8859-2');
?>
UTF-8 is not supported on windows platforms, so there the iconv workaround must be used:
<?php
setlocale(LC_ALL, 'hun_hun');
echo(iconv('ISO-8859-2', 'UTF-8',strftime('%Y. %B %d. %A')));
?>
The output is the same as before. Note that, the iconv first parameter is ISO-8859-2 not ISO-8859-1, because the locale is hungarian which uses 8859-2 codepage as default. It is needed for the right accents.
If you want use the same code for Windows and Linux platforms, the second one is the right option (the iconv trick), but the locale configuration must be different (Linux: hu_HU, windows: hun_hun), but in that case the UTF8 tag is not needed for the Linux config.
<?php
// Date string
$timestamp = strftime("%Y-%m-%d %H:%M:%S %Y");
// From this string ($timestamp) can we print
echo strftime("%a %d %b %H:%M:%S %Y", strtotime($timestamp))."<br/>";
echo strftime("%a %d %b %H:%M", strtotime($timestamp))."<br/>";
echo strftime("%Y-%m-%d %H:%M:%S", strtotime($timestamp))."<br/>";
echo strftime("%Y-%m-%d %H:%M", strtotime($timestamp))."<br/>";
echo strftime("%Y-%m-%d", strtotime($timestamp))."<br/>";
echo strftime("%a %d %b %Y", strtotime($timestamp))."<br/>";
/*And it will output
Wed 20 May 15:53:40 2009
Wed 20 May 15:53
2009-05-20 15:53:40
2009-05-20 15:53
2009-05-20
Wed 20 May 2009
*/
?>
This is so simple it has to be found in one of all the comments on all those different time functions. But since I didn't find it, here it is: Use this to convert between different time formats:
<?PHP
if (!function_exists('convertTime')) {
/** Converts time strings from one format into another using
* PHP formats.
*
* @param String $dformat Format to convert to
* @param String $sformat Format to convert from, e.g. format
* of $ts
* @param String $ts Time string to be converted
* @return String Supplied time translated to the format specified
* in $dformat
*/
function convertTime($dformat,$sformat,$ts) {
extract(strptime($ts,$sformat));
return strftime($dformat,mktime(
intval($tm_hour),
intval($tm_min),
intval($tm_sec),
intval($tm_mon)+1,
intval($tm_mday),
intval($tm_year)+1900
));
}
}
/*
* And for the test....
*/
echo convertTime('%Y-%m-%d','%d.%m.%Y','27.11.2009');
?>
This should print "2009-27-11".
I did not put much effort in this code. The task also seems "too simple to be neccessary". But as I said, I didn't find anything to help me with this.
Cheers,
Michael Z
I had a need to subtrackt an older time from current time to get the time between.
Example: If one has worked from 2009-03-16 11:33:54 to 2009-03-16 12:01:54 then he has worked X hours,minutes and seconds. I tried to find that X. And so - one solution would be:
<?php
$start_date = strtotime("2009-03-16 11:33:54"); //start date from database - date("Y-m-d H:i:s") made as UNIX timestamp
$end_date = strtotime("2009-03-16 12:01:54"); //end date from database - date("Y-m-d H:i:s") made as UNIX timestamp
$ajavahe = $end_date - $start_date;
$time_between = gmstrftime('%Hh %Mm %Ss', $ajavahe); //gmstrftime() deals with different timezones correctly. (If in example you would be situated in Estonia and you would use strftime() you get wrong answer off by 2 hrs, because timezone is GMT+2 - with gmstrftime() comes right answer.)
echo 'You have worked: '.$time_between;
?>
Hope that this one makes someones life easier :D
<?php
/*
* This function figures out what fiscal year a specified date is in.
* $inputDate - the date you wish to find the fiscal year for. (12/4/08)
* $fyStartDate - the month and day your fiscal year starts. (7/1)
* $fyEndDate - the month and day your fiscal year ends. (6/30)
* $fy - returns the correct fiscal year
*/
function calculateFiscalYearForDate($inputDate, $fyStart, $fyEnd){
$date = strtotime($inputDate);
$inputyear = strftime('%Y',$date);
$fystartdate = strtotime($fyStart.$inputyear);
$fyenddate = strtotime($fyEnd.$inputyear);
if($date < $fyenddate){
$fy = intval($inputyear);
}else{
$fy = intval(intval($inputyear) + 1);
}
return $fy;
}
// my fiscal year starts on July,1 and ends on June 30, so...
echo calculateFiscalYearForDate("5/15/08","7/1","6/30");
// returns 2008
echo calculateFiscalYearForDate("12/1/08","7/1","6/30");
// returns 2009
?>
for Arabic
<?php
setlocale(LC_ALL,'ar');
echo strftime('%A %d %B %Y');
?>
This is what worked in my case:
<?php
setlocale(LC_ALL, 'es_ES').': ';
echo iconv('ISO-8859-1', 'UTF-8', strftime('%A %d de %B de %Y', time()));
?>
it displays: miércoles 22 de octubre de 2008
For windows user:
If you unsuccessfully change date/time format to your locale country using xx_XX format, try using XXX format or ISO-639 country codes format.
See complete list for ISO-639 here: http://www.w3.org/WAI/ER/IG/ert/iso639.htm
For example:
<?php
setlocale(LC_ALL, 'IND');
echo strftime("Today in Indonesia is %A");
?>
Here's a simple version for date formating i use between displaying in HTML and converting back to MYSQL format:
<?php
function format_date($original='', $format="%m/%d/%Y") {
$format = ($format=='date' ? "%m-%d-%Y" : $format);
$format = ($format=='datetime' ? "%m-%d-%Y %H:%M:%S" : $format);
$format = ($format=='mysql-date' ? "%Y-%m-%d" : $format);
$format = ($format=='mysql-datetime' ? "%Y-%m-%d %H:%M:%S" : $format);
return (!empty($original) ? strftime($format, strtotime($original)) : "" );
}
?>
example (in HTML or webapp):
[grab from database]...
$dbase_stored_date = "2007-03-15";
$display_html_date = format_date($dbase_stored_date);
... displays as "03/15/2007"
example (saving form via on POST/GET):
$update_date = format_date($_POST['display_html_date'], 'mysql-date');
// converts back to '2007-03-15'
.... [your mysql update here]
Don't forget to sanitize your POST/GET's =)
Here is a function to convert dates before 1970, very useful if you are still using php 4 (it is supported in php5) :
<?php
# convert a date to special format
# $date is like 2000-01-01 00:00:00
# $format : refer to strftime function
function convert_date($date,$format) {
if($date=='0000-00-00 00:00:00' OR $date=='0000-00-00' OR $date=='' OR $date==NULL) {
return '';
}
else {
$year=substr($date,0,4);
if(phpversion() < 5.0 AND $year < 1970) {
$new_date=substr_replace($date,'1980',0,4); # we replace the year by a year after 1970
$new_format=eregi_replace('%a|%A|%u','',$format); # we remove days information from the format because they would be wrong
$new_date=strftime($new_format,strtotime($new_date)); # we convert the date
$new_date=eregi_replace('1980',$year,$new_date); # we put back the real year
return $new_date;
}
else {
return strftime($format,strtotime($date));
}
}
}
?>
A small function to get the first weekday of the month.
For example the first monday of the month, or the first friday, etc.
<?php
/**
*
* Gets the first weekday of that month and year
*
* @param int The day of the week (0 = sunday, 1 = monday ... , 6 = saturday)
* @param int The month (if false use the current month)
* @param int The year (if false use the current year)
*
* @return int The timestamp of the first day of that month
*
**/
function get_first_day($day_number=1, $month=false, $year=false)
{
$month = ($month === false) ? strftime("%m"): $month;
$year = ($year === false) ? strftime("%Y"): $year;
$first_day = 1 + ((7+$day_number - strftime("%w", mktime(0,0,0,$month, 1, $year)))%7);
return mktime(0,0,0,$month, $first_day, $year);
}
// this will output the first wednesday of january 2007 (wed 03-01-2007)
echo strftime("%a %d-%m-%Y", get_first_day(3, 1, 2007));
?>
note, that for some languages you MUST set LC_ALL instead of LC_TIME.
note that you further have to explicitly define your output-encoding (default is ISO-8859-1 [which makes problems for some languages])!
at least i expirienced this behaviour on a german WinXP-PHP4 environment:
<?php
// does not work - gives question marks:
setlocale(LC_TIME, 'RUS'); // ISO Alpha-3 is supported by xp
echo strftime('%A', time());
?>
<?php
// DOES work:
header('Content-Type: text/html; charset=UTF-8'); // you could also use another charset here if iconv isn't installed on your system.
echo setlocale(LC_ALL, 'RUS').': ';
echo iconv('windows-1251', 'UTF-8', strftime('%A', time()))."\n";
?>
This little function allows you to provide a reasonably human readable string and convert to a timestamp - see example in comments below.
I find it far more useful than having to remember all the '%' modifiers. Am also well aware of its failings but it works in a lot of the real life situations I've come across.
<?php
function AmazingStringFromTime($str, $nTimestamp = null)
{
// This function reads a human readable string representation of dates. e.g.
// DD MM YYYY => 01 07 1978
// DDD D MMM YY => Mon 1 Jul 78
$arrPairs = array(
"DDDD" => "%A",
"DDD" => "%a",
"DD" => "%d",
"D" => "%e", // has leading space: ' 1', ' 2', etc for single digit days
"MMMM" => "%B",
"MMM" => "%b",
"MM" => "%m",
"YYYY" => "%Y",
"YY" => "%y",
"HH" => "%H",
"hh" => "%I",
"mm" => "%M",
"ss" => "%S",
);
$str = str_replace(array_keys($arrPairs), array_values($arrPairs), $str);
return strftime($str, $nTimestamp);
}
?>
Function strftime() use the locales installed in your system (linux).
If you are like me and only leave in the system the locales you use normally (en_US and your own language locale, like es_ES), you'll only be able to use the locales installed. If your application is translated to other languages, you need these locales too.
The name of the locale in your system is important too. This can be a problem when you want to distribute the app.
If you have this locales in your system:
en_US/ISO-8859-1
en_US.UTF-8/UTF-8
es_ES/ISO-8859-1
es_ES@euro/ISO-8859-15
es_ES.UTF-8/UTF-8
es_ES@euro/UTF-8
and use setlocale('es_ES'), the result will use the iso-8859-1 charset even if you have all your system, files and configuration options in UTF-8. To receive content in UTF-8, in this example, you need to use setlocale('es_ES.UTF-8') or setlocale('es_ES.UTF-8@UTF-8').
The definition of locales can change from one system to another, and so the charset from the results.
(in addition to Andy's post)
To get a RFC 2822 date (used in RSS) of the current local time :
echo strftime ("%a, %d %b %Y %H:%M:%S %z") ;
Note: option %z / %Z - work different on Windows platform, for example
output of this code line can be:
Thu, 02 Nov 2006 09:54:59 Jerusalem Standard Time (on Windows)
Thu, 02 Nov 2006 09:54:59 +0200 (on Linux)
[red. It is much smarter to use date(DATE_RSS); here]
Under windows if you are using Japanese version, you must use the following code:
setlocale(LC_ALL, "Japanese_Japan.20932") for EUC
setlocale(LC_ALL, "Japanese_Japan.932") for SJIS
I found the following page that helped me with this issue:
http://moodle.org/mod/forum/discuss.php?d=8329
The following function implements the conversion specifiers which are not supported on Win32 platforms:
(Note: the specifiers %V, %G and %g can be implemented using other functions described in this section)
<?php
function strftime_win32($format, $ts = null) {
if (!$ts) $ts = time();
$mapping = array(
'%C' => sprintf("%02d", date("Y", $ts) / 100),
'%D' => '%m/%d/%y',
'%e' => sprintf("%' 2d", date("j", $ts)),
'%h' => '%b',
'%n' => "\n",
'%r' => date("h:i:s", $ts) . " %p",
'%R' => date("H:i", $ts),
'%t' => "\t",
'%T' => '%H:%M:%S',
'%u' => ($w = date("w", $ts)) ? $w : 7
);
$format = str_replace(
array_keys($mapping),
array_values($mapping),
$format
);
return strftime($format, $ts);
}
?>
To get a RFC 850 date (used in HTTP) of the current time:
gmstrftime ("%A %d-%b-%y %T %Z", time ());
This will get for example:
Friday 25-Jun-04 03:30:23 GMT
Please note that times in HTTP-headers _must_ be GMT, so use gmstrftime() instead of strftime().
Note that setting LC_TIME is not enough for some locales under Windows, e.g. Czech, because there are some characters not contained in default (US) character set like '�' (c with hook), '�' (r with hook).
If you run Apache as regular application and have set your locale to Czech (ControlPanel/RegionalOptions), there is no problem and 'September' is correctly translated as 'z���', 'Thursday' as '�tvrtek'.
But if you run Apache as service, you get 'z�r�', and 'ctvrtek'.
To get things work as you expect you must set LC_CTYPE beside LC_TIME, or set LC_ALL.
<?php
$locale = 'Czech_Czech.1250';
$res = setlocale( 'LC_CTYPE', $locale); //important
$res = setlocale( 'LC_TIME', $locale);
echo strftime( '%A %m. %B %Y', mktime( 0,0,0,9,6,2001));
?>
Locale names are OS dependent. HP-UX 11.0, for example, has three
German locales, de_DE.roman8, de_DE.iso88591, and
de_DE.iso885915@euro.
The command locale -a will display all available locales on a system.
So on HP-UX, to get German dates:
<?php
setlocale("LC_TIME", "de_DE.roman8");
print(strftime("%A\n"));
?>