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Date/Time Функции

Содержание

  • checkdate — Проверяет правильность даты по грегорианскому календарю
  • date_add — Псевдоним DateTime::add
  • date_create_from_format — Псевдоним DateTime::createFromFormat
  • date_create — Returns new DateTime object
  • date_date_set — Псевдоним DateTime::setDate
  • date_default_timezone_get — Gets the default timezone used by all date/time functions in a script
  • date_default_timezone_set — Sets the default timezone used by all date/time functions in a script
  • date_diff — Псевдоним DateTime::diff
  • date_format — Псевдоним DateTime::format
  • date_get_last_errors — Псевдоним DateTime::getLastErrors
  • date_interval_create_from_date_string — Псевдоним DateInterval::createFromDateString
  • date_interval_format — Псевдоним DateInterval::format
  • date_isodate_set — Псевдоним DateTime::setISODate
  • date_modify — Псевдоним DateTime::modify
  • date_offset_get — Псевдоним DateTime::getOffset
  • date_parse_from_format — Get info about given date
  • date_parse — Returns associative array with detailed info about given date
  • date_sub — Псевдоним DateTime::sub
  • date_sun_info — Returns an array with information about sunset/sunrise and twilight begin/end
  • date_sunrise — Returns time of sunrise for a given day and location
  • date_sunset — Returns time of sunset for a given day and location
  • date_time_set — Псевдоним DateTime::setTime
  • date_timestamp_get — Псевдоним DateTime::getTimestamp
  • date_timestamp_set — Псевдоним DateTime::setTimestamp
  • date_timezone_get — Псевдоним DateTime::getTimezone
  • date_timezone_set — Псевдоним DateTime::setTimezone
  • date — Форматирует системную дату/время
  • getdate — Возвращает информацию о дате/времени
  • gettimeofday — Возвращает текущее время
  • gmdate — Форматирует дату/время по Гринвичу
  • gmmktime — Возвращает метку времени Unix для времени по Гринвичу
  • gmstrftime — Форматирует дату/время по Гринвичу с учетом текущей локали
  • idate — Format a local time/date as integer
  • localtime — Возвращает системное время
  • microtime — Возвращает метку времени с микросекундами
  • mktime — Возвращает метку времени для заданной даты
  • strftime — Форматирует текущую дату/время с учетом текущей локали
  • strptime — Parse a time/date generated with strftime
  • strtotime — Преобразует текстовое представление даты на английском языке в метку времени Unix
  • time — Возвращает текущую метку времени
  • timezone_abbreviations_list — Псевдоним DateTimeZone::listAbbreviations
  • timezone_identifiers_list — Псевдоним DateTimeZone::listIdentifiers
  • timezone_location_get — Псевдоним DateTimeZone::getLocation
  • timezone_name_from_abbr — Returns the timezone name from abbrevation
  • timezone_name_get — Псевдоним DateTimeZone::getName
  • timezone_offset_get — Псевдоним DateTimeZone::getOffset
  • timezone_open — Returns new DateTimeZone object
  • timezone_transitions_get — Псевдоним DateTimeZone::getTransitions

User Contributed Notes
Date/Time Functions
luck dot lil dot leprechaun at gmail dot com
19-May-2009 10:53
This is an easily extendable and pretty way to output human-readable date differences such as "1 day 2 hours ago", "6 months ago", "3 years 7 months 14 days 1 hour 4 minutes 16 seconds" etc etc.
Change "$levels = 2;" to whatever you want. A value of 1 will limit to only one number in the result ("3 days ago"). A value of 3 would result in up to three ("3 days 1 hour 2 minutes ago")

It can be used in the following ways:
echo compare_dates($start_date,$end_date);
echo compare_dates($end_date,$start_date);
echo compare_dates($start_date); //end date will be assumed as time();

<?php
function compare_dates($date1, $date2 = time())
    {
   
$blocks = array(
        array(
'name'=>'year','amount'    =>    60*60*24*365    ),
        array(
'name'=>'month','amount'    =>    60*60*24*31    ),
        array(
'name'=>'week','amount'    =>    60*60*24*7    ),
        array(
'name'=>'day','amount'    =>    60*60*24    ),
        array(
'name'=>'hour','amount'    =>    60*60        ),
        array(
'name'=>'minute','amount'    =>    60        ),
        array(
'name'=>'second','amount'    =>    1        )
        );
   
   
$diff = abs($date1-$date2);
   
   
$levels = 2;
   
$current_level = 1;
   
$result = array();
    foreach(
$blocks as $block)
        {
        if (
$current_level > $levels) {break;}
        if (
$diff/$block['amount'] >= 1)
            {
           
$amount = floor($diff/$block['amount']);
            if (
$amount>1) {$plural='s';} else {$plural='';}
           
$result[] = $amount.' '.$block['name'].$plural;
           
$diff -= $amount*$block['amount'];
           
$current_level++;
            }
        }
    return
implode(' ',$result).' ago';
    }
?>

[EDIT BY danbrown AT php DOT net: Contains a bugfix supplied by (jorge AT dontspam DOT com) on 22-OCT-2009.]
Robb_Bean at gmx dot nospam dot net
18-Mar-2008 11:47
With PHP 5.1 and 5.2 the languages datetime support has changed. Although these functions should guess your local timezone settings, they may fail if using a default configuration in a "pre-5.1 way", which means setting no timezone for PHP. In the case PHP could not get a timezone it emits a E_STRICT warning. Note that this affects _all_ datetime functions and keep it in mind when porting software from previous versions to 5.1 or later! It may also confuse your error handling (this is the way I noticed that things have changed, since these changes are not documentated _here_).

References:

http://www.php.net/manual/de/migration51.datetime.php
http://www.php.net/manual/de/migration52.datetime.php
sagar
28-Feb-2008 04:53
<?php
####################################
# Provide week number and get start_timestamp and end_timestamp
#####################################

// this week number will come from the timeshare form
 
$week = 51;

$times = get_start_and_end_date_from_week($week);
$start_time = $times['start_timestamp'];
$end_time = $times['end_timestamp'];

function
get_start_and_end_date_from_week ($w)
{
   
$y = date("Y", time());
   
$o = 6; // week starts from sunday by default

   
$days = ($w - 1) * 7 + $o;

   
$firstdayofyear = getdate(mktime(0,0,0,1,1,$y));
    if (
$firstdayofyear["wday"] == 0) $firstdayofyear["wday"] += 7;
   
# in getdate, Sunday is 0 instead of 7
   
$firstmonday = getdate(mktime(0,0,0,1,1-$firstdayofyear["wday"]+1,$y));
   
$calcdate = getdate(mktime(0,0,0,$firstmonday["mon"], $firstmonday["mday"]+$days,$firstmonday["year"]));

   
$sday = $calcdate["mday"];
   
$smonth = $calcdate["mon"];
   
$syear = $calcdate["year"];
   
       
   
$timestamp['start_timestamp'] =  mktime(0, 0, 0, $smonth, $sday, $syear);
   
$timestamp['end_timestamp'] =  $timestamp['start_timestamp'] + (60*60*24*7);

    return
$timestamp;

}   
# function datefromweek
?>
nate at example dot com
05-Feb-2008 12:56
Here's my version of date diff that handles leap years, DST, and deals with the diff in terms of "human calculations". For example, this code does not assume that a year = 365.25 days, or that a month = 30/31 days. The results are exactly what a human being would determine as a good result.

<?php

/**
 * this code assumes php >= 5.1.0. if using < 5.1, read
 * php.net/strtotime and change the condition for checking
 * for failure from strtotime()
 */

// $t1, $t2: unix times, or strtotime parseable
// $precision: max number of units to output
// $abbr: if true, use "hr" instead of "hour", etc.
function date_diff ($t1, $t2, $precision = 6, $abbr = false) {
    if (
preg_match('/\D/', $t1) && ($t1 = strtotime($t1)) === false)
        return
false;

    if (
preg_match('/\D/', $t2) && ($t2 = strtotime($t2)) === false)
        return
false;

    if (
$t1 > $t2)
        list(
$t1, $t2) = array($t2, $t1);

   
$diffs = array(
       
'year' => 0, 'month' => 0, 'day' => 0,
       
'hour' => 0, 'minute' => 0, 'second' => 0,
    );

   
$abbrs = array(
       
'year' => 'yr', 'month' => 'mth', 'day' => 'day',
       
'hour' => 'hr', 'minute' => 'min', 'second' => 'sec'
   
);

    foreach (
array_keys($diffs) as $interval) {
        while (
$t2 >= ($t3 = strtotime("+1 ${interval}", $t1))) {
           
$t1 = $t3;
            ++
$diffs[$interval];
        }
    }

   
$stack = array();
    foreach (
$diffs as $interval => $num)
       
$stack[] = array($num, ($abbr ? $abbrs[$interval] : $interval) . ($num != 1 ? 's' : ''));

   
$ret = array();
    while (
count($ret) < $precision && ($item = array_shift($stack)) !== null) {
        if (
$item[0] > 0)
           
$ret[] = "{$item[0]} {$item[1]}";
    }

    return
implode(', ', $ret);
}

$t1 = 'Feb 4, 2008 12:16:00';
$t2 = 'Jul 3, 2006 16:15:30';

echo
date_diff($t1, $t2), "\n",
   
date_diff($t1, $t2, 3), "\n",
   
date_diff($t1, $t2, 2, true), "\n";

?>
stoicnluv at gmail dot com
05-Nov-2007 11:14
A better and accurate function to calculate the difference between 2 dates. Takes leap years and DST into consideration. Accepts string date or timestamp as arguments.

<?php
function date_diff($d1, $d2){
   
$d1 = (is_string($d1) ? strtotime($d1) : $d1);
   
$d2 = (is_string($d2) ? strtotime($d2) : $d2);

   
$diff_secs = abs($d1 - $d2);
   
$base_year = min(date("Y", $d1), date("Y", $d2));

   
$diff = mktime(0, 0, $diff_secs, 1, 1, $base_year);
    return array(
       
"years" => date("Y", $diff) - $base_year,
       
"months_total" => (date("Y", $diff) - $base_year) * 12 + date("n", $diff) - 1,
       
"months" => date("n", $diff) - 1,
       
"days_total" => floor($diff_secs / (3600 * 24)),
       
"days" => date("j", $diff) - 1,
       
"hours_total" => floor($diff_secs / 3600),
       
"hours" => date("G", $diff),
       
"minutes_total" => floor($diff_secs / 60),
       
"minutes" => (int) date("i", $diff),
       
"seconds_total" => $diff_secs,
       
"seconds" => (int) date("s", $diff)
    );
}

$a = date_diff("2006-11-01", "2007-11-01");

echo
"<pre>";
print_r($a);
echo
"</pre>";
?>

This example will output (if your timezone uses US DST):

Array
(
    [years] => 0
    [months_total] => 11
    [months] => 11
    [days_total] => 364
    [days] => 30
    [hours_total] => 8759
    [hours] => 23
    [minutes_total] => 525540
    [minutes] => 0
    [seconds_total] => 31532400
    [seconds] => 0
)

As you can see, the result is not exactly 1 year (less 1 hour) since Nov 1, 2006 is not DST while Nov 1, 2007 is DST.
venoel at rin dot ru
26-Oct-2007 10:33
May be useful for somebody. This function takes on daylight saving time

<?php
Function DateDiff($date1,$date2) {
 
$timedifference=$date2-$date1;
 
$corr=date("I",$date2)-date("I",$date1);
 
$timedifference+=$corr;
  return
$timedifference;
}
?>

Example:

<?php
$d1
=mktime(2,0,0,10,28,2007);
$d2=mktime(4,0,0,10,28,2007);
$period=DateDiff($d1,$d2);
printf("<br>%s",date("I d.m.Y H:i",$d1));
printf("<br>%u hour",$period/3600);
printf("<br>%s",date("I d.m.Y H:i",$d2));
?>

Getting 2 hour instead 3.
koch.ro
17-Oct-2007 07:42
Not really elegant, but tells you, if your installed timezonedb is the most recent:

<?php
class TestDateTimeTimezonedbVersion extends PHPUnit_Framework_TestCase
{
    public function
testTimezonedbIsMostRecent()
    {
       
ini_set( 'date.timezone', 'Europe/Berlin' );
       
ob_start();                                                                                                       
       
phpinfo(INFO_MODULES);
       
$info = ob_get_contents();                                                                                        
       
ob_end_clean();
       
$start = strpos( $info, 'Timezone Database Version' ) + 29;

       
$this->assertTrue( FALSE !== $start, 'Seems there is no timezone DB installed' );

       
$end   = strpos( $info, "\n", $start );
       
$installedVersion = substr( $info, $start, $end - $start );

       
exec( 'pecl remote-info timezonedb', &$output );
       
$availableVersion = substr( $output[2], 12 );

       
$this->assertEquals( $availableVersion, $installedVersion,
       
'The installed timezonedb is not actual. Installed: '.$installedVersion
       
.' available: '.$availableVersion
       
);
    }
}
?>
aquatakat at telus dot net
24-Sep-2007 08:25
I wrote a simple script to format a duration in seconds. Give the function some value in seconds and it will return an array.

<?php

function format_duration($seconds) {

   
$periods = array(
       
'centuries' => 3155692600,
       
'decades' => 315569260,
       
'years' => 31556926,
       
'months' => 2629743,
       
'weeks' => 604800,
       
'days' => 86400,
       
'hours' => 3600,
       
'minutes' => 60,
       
'seconds' => 1
   
);

   
$durations = array();

    foreach (
$periods as $period => $seconds_in_period) {
        if (
$seconds >= $seconds_in_period) {
           
$durations[$period] = floor($seconds / $seconds_in_period);
           
$seconds -= $durations[$period] * $seconds_in_period;
        }
    }
   
    return
$durations;

}

echo
format_duration(864);

/*
[minutes] => 14
[seconds] => 24
*/

echo format_duration(3600);

/*
[hours] => 1
*/

echo format_duration(11111111);

/*
[months] => 4
[days] => 6
[hours] => 20
[minutes] => 28
[seconds] => 59
*/

?>
Darren Edwards
06-Sep-2007 03:54
I was looking for a solution where I could return the number of days, hours, Minutes and seconds between two entries in a table.
DATE_DIFF is not running on my mysql server as my provider uses mysql version 4.0.25
Solution was to use to days and std time functions to calculate the difference in one call.
The fields stored in the table(report_table) are
time(00:00:00),
date(0000-00-00) and record(enum) which tells the app the type of log stored. EG start or end of a report.

SELECT
(TO_DAYS( `end`.`date` ) - TO_DAYS( `start`.`date` ))
-
( second( `end`.`time` ) + (minute( `end`.`time` )*60) + (hour( `end`.`time` )*3600)
<
 second( `start`.`time` ) + (minute( `start`.`time` )*60) + (hour( `start`.`time` )*3600))
AS `days` ,
SEC_TO_TIME(
(second( `end`.`time` ) + (minute( `end`.`time` )*60) + (hour( `end`.`time` )*3600) )
-
(second( `start`.`time` ) + (minute( `start`.`time` )*60) + (hour( `start`.`time` )*3600) )
 ) AS `hms`,
`start`.`time` as `start`,
`end`.`time`  as `end`

FROM `report_table` AS `start` , `report_table` AS `end`
AND `start`.`record` = 'Report Begin'
AND `end`.`record` = 'Report End'
LIMIT 1

If there is no end of report then it will not return a result, as you would expect.
Leopoldo A dot Oducado (poducado at comfsm dot fm)
16-Feb-2007 03:50
Here is my function to count the number days, weeks, months, and year. I tried it below 1970 and it works.

<?php
function datecal($date,$return_value)
{
$date = explode("/", $date);
$month_begin = $date[0];
$month_begin_date = $date[1];
$year1 = $date[2];
$month_end = date("n");
$month_end_date = date("j");
$year2 = date("Y");
$days_old = 0;
$years_old = 0;
$months_old = 0;
if(
$month_begin==12)
{
 
$month = 1;
 
$year = $year1+1;
}
else
{
 
$month = $month_begin+1;
 
$year = $year1;
}
$begin_plus_days = cal_days_in_month(CAL_GREGORIAN, $month_begin, $year1) - $month_begin_date;
$end_minus_days = cal_days_in_month(CAL_GREGORIAN, $month_end, $year2) - $month_end_date;
while (
$year <= $year2)
{   
     if(
$year == $year2)
    {
     
$days_old = $days_old + cal_days_in_month(CAL_GREGORIAN, $month, $year);    
      if(
$month < $month_end)
        {
        
$months_old = $months_old + 1;   
        
$month = $month + 1;
        }
          elseif (
$month==$month_end and $month_end_date >= $month_begin_date)
            {
        
$year = $year2+1;   
        }
      else
        {   
        
$year = $year2+1;   
        }
    }
    else
    {
    
$days_old = $days_old + cal_days_in_month(CAL_GREGORIAN, $month, $year);
         if (
$month <= 11)
            {
        
$month = $month + 1;
        
$months_old = $months_old + 1;   
            }
         else
            {
        
$month = 1;
        
$year = $year + 1;
        
$months_old = $months_old + 1;       
            }    
    }
}
$days_old = ($days_old + $begin_plus_days) - $end_minus_days;
if(
$return_value == "d")
  { return
$days_old; }
elseif (
$return_value == "w")
  { return
intval($days_old/7); }
elseif (
$return_value == "m")
  { return
$months_old; }
elseif (
$return_value == "y")
  { return
intval($months_old/12); }
}

echo
datecal("08/13/1975","m");
?>
bgold at matrix-consultants dot com
17-Jan-2007 01:08
When debugging code that stores date/time values in a database, you may find yourself wanting to know the date/time that corresponds to a given unix timestamp, or the timestamp for a given date & time.

The following script will do the conversion either way.  If you give it a numeric timestamp, it will display the corresponding date and time.  If you give it a date and time (in almost any standard format), it will display the timestamp.

All conversions are done for your locale/time zone.

<?php
       
while (true)
        {
               
// Read a line from standard in.
               
echo "enter time to convert: ";
               
$inline = fgets(STDIN);
               
$inline = trim($inline);
                if (
$inline == "" || $inline == ".")
                        break;

               
// See if the line is a date.
               
$pos = strpos($inline, "/");
                if (
$pos === false) {
                       
// not a date, should be an integer.
                       
$date = date("m/d/Y G:i:s", $inline);
                        echo
"int2date: $inline -> $date\n";
                } else {
                       
$itime = strtotime($inline);
                        echo
"date2int: $inline -> $itime\n";
                }
        }
?>
andreencinas at yahoo dot com dot br
28-Sep-2005 12:08
<?php
      
//function like dateDiff Microsoft
       //not error in year Bissesto

      
function dateDiff($interval,$dateTimeBegin,$dateTimeEnd) {
        
//Parse about any English textual datetime
         //$dateTimeBegin, $dateTimeEnd

        
$dateTimeBegin=strtotime($dateTimeBegin);
         if(
$dateTimeBegin === -1) {
           return(
"..begin date Invalid");
         }

        
$dateTimeEnd=strtotime($dateTimeEnd);
         if(
$dateTimeEnd === -1) {
           return(
"..end date Invalid");
         }

        
$dif=$dateTimeEnd - $dateTimeBegin;

         switch(
$interval) {
           case
"s"://seconds
              
return($dif);

           case
"n"://minutes
              
return(floor($dif/60)); //60s=1m

          
case "h"://hours
              
return(floor($dif/3600)); //3600s=1h

          
case "d"://days
              
return(floor($dif/86400)); //86400s=1d

          
case "ww"://Week
              
return(floor($dif/604800)); //604800s=1week=1semana

          
case "m": //similar result "m" dateDiff Microsoft
              
$monthBegin=(date("Y",$dateTimeBegin)*12)+
                
date("n",$dateTimeBegin);
              
$monthEnd=(date("Y",$dateTimeEnd)*12)+
                
date("n",$dateTimeEnd);
              
$monthDiff=$monthEnd-$monthBegin;
               return(
$monthDiff);

           case
"yyyy": //similar result "yyyy" dateDiff Microsoft
              
return(date("Y",$dateTimeEnd) - date("Y",$dateTimeBegin));

           default:
               return(
floor($dif/86400)); //86400s=1d
        
}

       }
?>
glashio at xs4all dot nl
27-Sep-2005 07:46
Calculate Sum BusinessDays (Mon till Fri) between two date's :

<?php
function businessdays($begin, $end) {
   
$rbegin = is_string($begin) ? strtotime(strval($begin)) : $begin;
   
$rend = is_string($end) ? strtotime(strval($end)) : $end;
    if (
$rbegin < 0 || $rend < 0)
        return
0;

   
$begin = workday($rbegin, TRUE);
   
$end = workday($rend, FALSE);

    if (
$end < $begin) {
       
$end = $begin;
       
$begin = $end;
    }

   
$difftime = $end - $begin;
   
$diffdays = floor($difftime / (24 * 60 * 60)) + 1;

    if (
$diffdays < 7) {
       
$abegin = getdate($rbegin);
       
$aend = getdate($rend);
        if (
$diffdays == 1 && ($astart['wday'] == 0 || $astart['wday'] == 6) && ($aend['wday'] == 0 || $aend['wday'] == 6))
            return
0;
       
$abegin = getdate($begin);
       
$aend = getdate($end);
       
$weekends = ($aend['wday'] < $abegin['wday']) ? 1 : 0;
    } else
       
$weekends = floor($diffdays / 7);
    return
$diffdays - ($weekends * 2);
}

function
workday($date, $begindate = TRUE) {
   
$adate = getdate($date);
   
$day = 24 * 60 * 60;
    if (
$adate['wday'] == 0) // Sunday
       
$date += $begindate ? $day : -($day * 2);
    elseif (
$adate['wday'] == 6) // Saterday
       
$date += $begindate ? $day * 2 : -$day;
    return
$date;
}
?>
daniel at globalnetstudios dot com
08-Jun-2005 06:49
This dateDiff() function can take in just about any timestamp, including UNIX timestamps and anything that is accepted by strtotime(). It returns an array with the ability to split the result a couple different ways. I built this function to suffice any datediff needs I had. Hope it helps others too.

<?php
 
/********* dateDiff() function **********
   * returns Array of Int values for difference between two dates
   * $date1 > $date2 --> positive integers are returned
   * $date1 < $date2 --> negative integers are returned
   *
   * $split recognizes the following:
   *   'yw' = splits up years, weeks and days (default)
   *   'y'  = splits up years and days
   *   'w'  = splits up weeks and days
   *   'd'  = total days
   *
   * examples:
   *   $dif1 = dateDiff() or dateDiff('yw')
   *   $dif2 = dateDiff('y')
   *   $dif3 = dateDiff('w')
   *   $dif4 = dateDiff('d')
   *
   * assuming dateDiff returned 853 days, the above
   * examples would have a print_r output of:
   *   $dif1 == Array( [y] => 2 [w] => 17 [d] => 4 )
   *   $dif2 == Array( [y] => 2 [d] => 123 )
   *   $dif3 == Array( [w] => 121 [d] => 6 )
   *   $dif4 == Array( [d] => 847 )
   *
   * note: [h] (hours), [m] (minutes), [s] (seconds) are always returned as elements of the Array
   */
 
function dateDiff($dt1, $dt2, $split='yw') {
   
$date1 = (strtotime($dt1) != -1) ? strtotime($dt1) : $dt1;
   
$date2 = (strtotime($dt2) != -1) ? strtotime($dt2) : $dt2;
   
$dtDiff = $date1 - $date2;
   
$totalDays = intval($dtDiff/(24*60*60));
   
$totalSecs = $dtDiff-($totalDays*24*60*60);
   
$dif['h'] = $h = intval($totalSecs/(60*60));
   
$dif['m'] = $m = intval(($totalSecs-($h*60*60))/60);
   
$dif['s'] = $totalSecs-($h*60*60)-($m*60);
   
// set up array as necessary
   
switch($split) {
    case
'yw': # split years-weeks-days
     
$dif['y'] = $y = intval($totalDays/365);
     
$dif['w'] = $w = intval(($totalDays-($y*365))/7);
     
$dif['d'] = $totalDays-($y*365)-($w*7);
      break;
    case
'y': # split years-days
     
$dif['y'] = $y = intval($totalDays/365);
     
$dif['d'] = $totalDays-($y*365);
      break;
    case
'w': # split weeks-days
     
$dif['w'] = $w = intval($totalDays/7);
     
$dif['d'] = $totalDays-($w*7);
      break;
    case
'd': # don't split -- total days
     
$dif['d'] = $totalDays;
      break;
    default:
      die(
"Error in dateDiff(). Unrecognized \$split parameter. Valid values are 'yw', 'y', 'w', 'd'. Default is 'yw'.");
    }
    return
$dif;
  }
?>
mail at completeideas dot com
06-Jun-2005 08:55
For those who are using pre MYSQL 4.1.1, you can use:

TO_DAYS([Date Value 1])-TO_DAYS([Date Value 2])

For the same result as:

DATEDIFF([Date Value 1],[Date Value 2])
mincklerstraat at softhome dot net
11-Oct-2004 08:43
Before you get too advanced using date functions, be sure also to see the calendar functions at https://doc0.ru/phpe/ref.calendar.php .
nickaubert at america's biggest isp dot com
12-Apr-2004 08:13
I ran into an issue using a function that loops through an array of dates where the keys to the array are the Unix timestamp for midnight for each date.  The loop starts at the first timestamp, then incremented by adding 86400 seconds (ie. 60 x 60 x 24).  However, Daylight Saving Time threw off the accuracy of this loop, since certain days have a duration other than 86400 seconds.  I worked around it by adding a couple of lines to force the timestamp to midnight at each interval.

<?php
  $ONE_DAY
= 90000;   // can't use 86400 because some days have one hour more or less
 
for ( $each_timestamp = $start_time ; $each_timestamp <= $end_time ; $each_timestamp +=  $ONE_DAY) {

   
/*  force midnight to compensate for daylight saving time  */
   
$this_timestamp_array = getdate( $each_timestamp );
   
$each_timestamp = mktime ( 0 , 0 , 0 , $this_timestamp_array[mon] , $this_timestamp_array[mday] , $this_timestamp_array[year] );

    
// do some stuff...
 
}
?>
php at sarge dot ch
28-Jan-2004 12:58
Additional thisone here (didn't test it yet but should work :D):

<?php
/**
 * Calculates the Difference between two timestamps
 *
 * @param integer $start_timestamp
 * @param integer $end_timestamp
 * @param integer $unit (default 0)
 * @return string
 * @access public
 */
function dateDifference($start_timestamp,$end_timestamp,$unit= 0){
 
$days_seconds_star= (23 * 56 * 60) + 4.091; // Star Day
 
$days_seconds_sun= 24 * 60 * 60; // Sun Day
 
$difference_seconds= $end_timestamp - $start_timestamp;
  switch(
$unit){
    case
3: // Days
     
$difference_days= round(($difference_seconds / $days_seconds_sun),2);
      return
'approx. '.$difference_hours.' Days';
    case
2: // Hours
     
$difference_hours= round(($difference_seconds / 3600),2);
      return
'approx. '.$difference_hours.' Hours';
    break;
    case
1: // Minutes
     
$difference_minutes= round(($difference_seconds / 60),2);
      return
'approx. '.$difference_minutes.' Minutes';
    break;
    default:
// Seconds
     
if($difference_seconds > 1){
        return
$difference_seconds.' Seconds';
      }
      else{
        return
$difference_seconds.' Second';
      }
  }
}
?>
php at elmegil dot net
20-Dec-2003 06:40
A much easier way to do days diff is to use Julian Days from the Calendar functions:

$start = gregoriantojd($smon, $sday, $syear);
$end = gregoriantojd($emon, $eday, $eyear);
$daysdiff = $end - $start;

You can see the obvious ways to wrap a function around that.
garyc at earthling dot net
19-Mar-2003 04:08
I needed to calculate the week number from a given date and vice versa, where the week starts with a Monday and the first week of a year may begin the year before, if the year begins in the middle of the week (Tue-Sun). This is the way weekly magazines calculate their issue numbers.

Here are two functions that do exactly that:

Hope somebody finds this useful.

Gary

<?php
/*  w e e k n u m b e r  -------------------------------------- //
weeknumber returns a week number from a given date (>1970, <2030)
Wed, 2003-01-01 is in week 1
Mon, 2003-01-06 is in week 2
Wed, 2003-12-31 is in week 53, next years first week
Be careful, there are years with 53 weeks.
// ------------------------------------------------------------ */

function weeknumber ($y, $m, $d) {
   
$wn = strftime("%W",mktime(0,0,0,$m,$d,$y));
   
$wn += 0; # wn might be a string value
   
$firstdayofyear = getdate(mktime(0,0,0,1,1,$y));
    if (
$firstdayofyear["wday"] != 1)    # if 1/1 is not a Monday, add 1
       
$wn += 1;
    return (
$wn);
}   
# function weeknumber

/*  d a t e f r o m w e e k  ---------------------------------- //
From a weeknumber, calculates the corresponding date
Input: Year, weeknumber and day offset
Output: Exact date in an associative (named) array
2003, 12, 0: 2003-03-17 (a Monday)
1995,  53, 2: 1995-12-xx
...
// ------------------------------------------------------------ */

function datefromweek ($y, $w, $o) {

   
$days = ($w - 1) * 7 + $o;

   
$firstdayofyear = getdate(mktime(0,0,0,1,1,$y));
    if (
$firstdayofyear["wday"] == 0) $firstdayofyear["wday"] += 7;
# in getdate, Sunday is 0 instead of 7
   
$firstmonday = getdate(mktime(0,0,0,1,1-$firstdayofyear["wday"]+1,$y));
   
$calcdate = getdate(mktime(0,0,0,$firstmonday["mon"], $firstmonday["mday"]+$days,$firstmonday["year"]));

   
$date["year"] = $calcdate["year"];
   
$date["month"] = $calcdate["mon"];
   
$date["day"] = $calcdate["mday"];

    return (
$date);

}   
# function datefromweek
?>
brighn (a) yahoo (.) com
03-Jan-2003 05:46
I needed a function that determined the last Sunday of the month. Since it's made for the website's "next meeting" announcement, it goes based on the system clock; also, if today is between Sunday and the end of the month, it figures out the last Sunday of *next* month. lastsunday() takes no arguments and returns the date as a string in the form "January 26, 2003". I could probably have streamlined this quite a bit, but at least it's transparent code. =)

<?php
 
/* The two functions calculate when the next meeting will
     be, based on the assumption that the meeting will be on
     the last Sunday of the month. */ 

 
function getlast($mon, $year) {
   
$daysinmonth = array(31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31);
   
$days = $daysinmonth[$mon-1];
    if (
$mon == 2 && ($year % 4) == 0 && (($year % 100) != 0 ||
    (
$year % 400) == 0)) $days++;
    if (
$mon == 2 && ($year % 4) == 0 && ($year % 1000) != 0) $days++;
   
$lastday = getdate(mktime(0,0,0,$mon,$days,$year));
   
$wday = $lastday['wday'];
    return
getdate(mktime(0,0,0,$mon,$days-$wday,$year));
  }

  function
lastsunday() {
   
$today = getdate();
   
$mon = $today['mon'];
   
$year = $today['year'];
   
$mday = $today['mday'];
   
$lastsun = getlast($mon, $year);
   
$sunday = $lastsun['mday'];
    if (
$sunday < $mday) {
     
$mon++;
      if (
$mon = 13) {
       
$mon = 1;
       
$year++;
      }
     
$lastsun = getlast($mon, $year);
     
$sunday = $lastsun['mday'];
    }
   
$nextmeeting = getdate(mktime(0,0,0,$mon,$sunday,$year));
   
$month = $nextmeeting['month'];
   
$mday = $nextmeeting['mday'];
   
$year = $nextmeeting['year'];
    return
"$month $mday, $year";
  }
?>
nightowl at NOS-PA-M dot uk2 dot net
30-Jul-2002 05:59
I wanted to find all records in my database which match the current week (for a call-back function). I made up this function to find the start and end of the current week :

<?php
function week($curtime) {
   
   
$date_array = getdate (time());
   
$numdays = $date_array["wday"];
   
   
$startdate = date("Y-m-d", time() - ($numdays * 24*60*60));
   
$enddate = date("Y-m-d", time() + ((7 - $numdays) * 24*60*60));

   
$week['start'] = $startdate;
   
$week['end'] = $enddate;
   
    return
$week;
   
}
?>
php-contrib at i-ps dot nospam dot net
30-Jan-2002 02:07
Someone may find this info of some use:

Rules for calculating a leap year:

1) If the year divides by 4, it is a leap year (1988, 1992, 1996 are leap years)
2) Unless it divides by 100, in which case it isn't (1900 divides by 4, but was not a leap year)
3) Unless it divides by 400, in which case it is actually a leap year afterall (So 2000 was a leap year).

In practical terms, to work out the number of days in X years, multiply X by 365.2425, rounding DOWN to the last whole number, should give you the number of days.

The result will never be more than one whole day inaccurate, as opposed to multiplying by 365, which, over more years, will create a larger and larger deficit.
th at definitynet dot com
11-Jan-2001 07:00
I had some problems with dates between mySQL and PHP.  PHP had all these great date functions but I wanted to store a usable value in my database tables. In this case I was using TIMESTAMP(14)  <or 'YYYYMMDDHHMMSS'>.
This is perhaps the easiest way I have found to pull the PHP usable UNIX Datestamp from my mySQL datestamp stored in the tables:

Use the mySQL UNIX_TIMESTAMP() function in your SQL definition string. i.e.

$sql= "SELECT field1, field2, UNIX_TIMESTAMP(field3) as your_date
          FROM your_table
          WHERE field1 = '$value'";

The query will return a temp table with coulms "field1" "Field2" "your_date"

The "your_date" will be formatted in a UNIX TIMESTAMP!  Now you can use the PHP date() function to spew out nice date formats.

Sample using above $sql:
20010111002747  = Date Stored on mySQL table (TIMESTAMP(14))
979172867  = value returned as your_date in sql stmt (UNIX_TIMESTAMP)

if we use $newdate = date("F jS, Y -- g:ia", $row["your_date"]);
   --(after fetching our array from the sql results of course)--

echo "$newdate";              --Will produce:
January 11th, 2001 -- 12:27am

Hope this helps someone out there!
 

 
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