Date/Time 函数
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time

(PHP 4, PHP 5)

time — 返回当前的 Unix 时间戳

说明

int time ( void )

返回自从 Unix 纪元（格林威治时间 1970 年 1 月 1 日 00:00:00）到当前时间的秒数。

Tip

自 PHP 5.1 起在 $_SERVER['REQUEST_TIME'] 中保存了发起该请求时刻的时间戳。

Example #1 time() 例子

<?php
$nextWeek = time() + (7 * 24 * 60 * 60);
                   // 7 days; 24 hours; 60 mins; 60secs
echo 'Now:       '. date('Y-m-d') ."\n";
echo 'Next Week: '. date('Y-m-d', $nextWeek) ."\n";
?>

以上例程的输出类似于：

Now:       2005-03-30
Next Week: 2005-04-07

参见 date() 和 microtime()。

范例

Example #2 time() example

<?php
$nextWeek = time() + (7 * 24 * 60 * 60);
                   // 7 days; 24 hours; 60 mins; 60secs
echo 'Now:       '. date('Y-m-d') ."\n";
echo 'Next Week: '. date('Y-m-d', $nextWeek) ."\n";
// or using strtotime():
echo 'Next Week: '. date('Y-m-d', strtotime('+1 week')) ."\n";
?>

以上例程的输出类似于：

Now:       2005-03-30
Next Week: 2005-04-06
Next Week: 2005-04-06

注释

Tip

Timestamp of the start of the request is available in $_SERVER['REQUEST_TIME'] since PHP 5.1.

参见

Date/Time 函数
在线手册：中文 英文
PHP手册
PHP手册 - N: 返回当前的 Unix 时间戳

用户评论:

relentless2712 at gmail dot com (06-Apr-2012 04:37)

-- RE: holdoffhunger at gmail dot com --

An easy way to find the timestamp for the following month is to use mktime!

<?php

$old_timestamp = 1331835943; // Thurs 15th May 2012

$my_month = date("m",$old_timestamp)+1;

$my_year = date("y",$old_timestamp);

/*
it doesnt matter if $my_month is 13. mktime will automatically, adjust the year accordingly
*/

$new_timestamp = mktime(0,0,0,$my_month,1,$my_year);

//Result: $new_timestamp = 1333256400 (Sun, 1 Apr, 2012)

?>

Or, for simplification purposes;

<?php

$old_timestamp = 1331835943; // Thurs 15th May 2012
$new_timestamp = mktime(0,0,0,date("m",$old_timestamp)+1,1,date("y",$old_timestamp)); //1333256400 (Sun, 1 Apr, 2012)

?>

Anonymous (05-Apr-2012 08:12)

For scripts that take a long time, the easiest way to find how how long the execution took is this:
<?php
$timeTaken = time() - $_SERVER['REQUEST_TIME'];
echo "This script took $timeTaken to run.";
?>
Obviously this is only useful if a script takes multiple seconds (I wrote one that logged into a site and scraped info from it and it can take up to a minute)

holdoffhunger at gmail dot com (16-Mar-2012 02:29)

Something I often want to do is find out the first of the next month and to get the time() result for it.  By using a combination of date() and strtotime(), you can do that:

<?php

        // by: holdoffhunger@gmail.com

        // Example Time() Integer (for Thu, 15 Mar, 2012)

    $time_to_handle_for_next_month_conversion = 1331835943;

        // Date Conversions
   
    $interpretted_day = date('d', $time_to_handle_for_next_month_conversion);
    $interpretted_month = date('F', $time_to_handle_for_next_month_conversion);
    $interpretted_month_lowercased = strtolower($interpretted_month);
    $interpretted_year = date('Y', $time_to_handle_for_next_month_conversion);

        // Preset Day

    $new_day = 1;

        // Handle Case: December
   
    if($interpretted_month_lowercased == "december")
    {
        $new_month = "January";
        $new_year = $interpretted_year + 1;
    }
    else
    {

        // Handle All Other Cases

        switch($interpretted_month_lowercased)
        {
            case 'january':
                $new_month = "February";
                break;
               
            case 'february':
                $new_month = "March";
                break;
               
            case 'march':
                $new_month = "April";
                break;
               
            case 'april':
                $new_month = "May";
                break;
               
            case 'may':
                $new_month = "June";
                break;
               
            case 'june':
                $new_month = "July";
                break;
               
            case 'july':
                $new_month = "August";
                break;
               
            case 'august':
                $new_month = "September";
                break;
               
            case 'september':
                $new_month = "October";
                break;
               
            case 'october':
                $new_month = "November";
                break;
               
            case 'november':
                $new_month = "December";
                break;
        }
   
        $new_year = $interpretted_year;
    }

    $new_date_string =         $new_day        . " " .
                    $new_month        . " " .
                    $new_year;
                   
        // Results
                   
    $first_day_of_the_next_month_time_integer = strtotime($new_date_string);

        // Result = 1333256400 (Sun, 1 Apr, 2012)

?>

tav (06-Jan-2012 12:06)

Calculates the difference between $start and $s, returns a formatted string Xd Yh Zm As, e.g. 15d 23h 54m 31s. Empty sections will be stripped, returning 12d 4s, not 12d 0h 0m 4s.

Argument order (begin date, end date) doesn't matter.

<?php

function time_diff_conv($start, $s) {
    $t = array( //suffixes
        'd' => 86400,
        'h' => 3600,
        'm' => 60,
    );
    $s = abs($s - $start);
    foreach($t as $key => &$val) {
        $$key = floor($s/$val);
        $s -= ($$key*$val);
        $string .= ($$key==0) ? '' : $$key . "$key ";
    }
    return $string . $s. 's';
}

?>

instantcarma2000 at yahoo dot se (14-Oct-2011 10:54)

This is a very basic and simple function to display either min -OR- hrs and min -OR- days and hrs -OR- days depending on how many seconds are given.

Example use:

<?php
$td = time_diff($timestamp1-$timestamp2); // has to be a positive result
$td .= ($td=="now")? "":" ago"; // in this example "ago"
echo $td;

function time_diff($s){
    $m=0;$hr=0;$d=0;$td="now";
    if($s>59) {
        $m = (int)($s/60);
        $s = $s-($m*60); // sec left over
        $td = "$m min";
    }
    if($m>59){
        $hr = (int)($m/60);
        $m = $m-($hr*60); // min left over
        $td = "$hr hr"; if($hr>1) $td .= "s";
        if($m>0) $td .= ", $m min";
    }
    if($hr>23){
        $d = (int)($hr/24);
        $hr = $hr-($d*24); // hr left over
        $td = "$d day"; if($d>1) $td .= "s";
        if($d<3){
            if($hr>0) $td .= ", $hr hr"; if($hr>1) $td .= "s";
        }
    }
    return $td;
}
?>

k7 dot india at gmail dot com (26-Aug-2011 06:57)

Here's a simple script to do arithmetic operations on date/time.
You can add/sub time in terms of Hour,Minutes,Seconds
 
<?php

echo $date = date("Y-m-d H:i:s");echo "\n";

$original=time($date);

$hr  = 25;
$min = 46;
$sec = 77;

$modified = $original+$sec+($min*60)+($hr*60*60);

echo date("Y-m-d H:i:s",$modified);echo "\n";

/* This'll outputs ...
 
2011-08-26 10:34:16
2011-08-27 12:21:33
*/

?>

dev dot ivangc at gmail dot com (05-Aug-2011 11:05)

Here a class extension to get the a datetime in the "X time ago" format easily.

<?php
class Cokidoo_DateTime extends DateTime {
   
    protected $strings = array(
        'y' => array('1 year ago', '%d years ago'),
        'm' => array('1 month ago', '%d months ago'),
        'd' => array('1 day ago', '%d days ago'),
        'h' => array('1 hour ago', '%d hours ago'),
        'i' => array('1 minute ago', '%d minutes ago'),
        's' => array('now', '%d secons ago'),
    );
   
    /**
     * Returns the difference from the current time in the format X time ago
     * @return string
     */
    public function __toString() {
        $now = new DateTime('now');
        $diff = $this->diff($now);
       
        foreach($this->strings as $key => $value){
            if( ($text = $this->getDiffText($key, $diff)) ){
                return $text;
            }
        }
        return '';
    }
   
    /**
     * Try to construct the time diff text with the specified interval key
     * @param string $intervalKey A value of: [y,m,d,h,i,s]
     * @param DateInterval $diff
     * @return string|null
     */
    protected function getDiffText($intervalKey, $diff){
        $pluralKey = 1;
        $value = $diff->$intervalKey;
        if($value > 0){
            if($value < 2){
                $pluralKey = 0;
            }
            return sprintf($this->strings[$intervalKey][$pluralKey], $value);
        }
        return null;
    }
}
?>

How to use:
<?php
$date = new Cokidoo_Datetime('2011-01-01');
echo $date;
?>

residualenvy at gmail dot com (11-Mar-2011 11:34)

My take on a function to find the differences between a timestamp and current time.

Format: findTime($sometime['stamp'], '%d Days, %h Hours, %m Minutes');

Always use plural it will auto correct on singular results.  You don't have to include all %d,%m,%h you may include only one.  To get Total Hours remaining(including days) use %ho.  To get Total Minutes remaining(including hours and days) use %mo.  Take a look at the format I assumed to make any changes.

<?php
function findTime($timestamp, $format) {       
        $difference = $timestamp - time();
        if($difference < 0)
            return false;
        else{
       
            $min_only = intval(floor($difference / 60));
            $hour_only = intval(floor($difference / 3600));
           
            $days = intval(floor($difference / 86400));
            $difference = $difference % 86400;
            $hours = intval(floor($difference / 3600));
            $difference = $difference % 3600;
            $minutes = intval(floor($difference / 60));
            if($minutes == 60){
                $hours = $hours+1;
                $minutes = 0;
            }
           
            if($days == 0){
                $format = str_replace('Days', '?', $format);
                $format = str_replace('Ds', '?', $format);
                $format = str_replace('%d', '', $format);
            }
            if($hours == 0){
                $format = str_replace('Hours', '?', $format);
                $format = str_replace('Hs', '?', $format);
                $format = str_replace('%h', '', $format);
            }
            if($minutes == 0){
                $format = str_replace('Minutes', '?', $format);
                $format = str_replace('Mins', '?', $format);
                $format = str_replace('Ms', '?', $format);       
                $format = str_replace('%m', '', $format);
            }
           
            $format = str_replace('?,', '', $format);
            $format = str_replace('?:', '', $format);
            $format = str_replace('?', '', $format);
           
            $timeLeft = str_replace('%d', number_format($days), $format);       
            $timeLeft = str_replace('%ho', number_format($hour_only), $timeLeft);
            $timeLeft = str_replace('%mo', number_format($min_only), $timeLeft);
            $timeLeft = str_replace('%h', number_format($hours), $timeLeft);
            $timeLeft = str_replace('%m', number_format($minutes), $timeLeft);
               
            if($days == 1){
                $timeLeft = str_replace('Days', 'Day', $timeLeft);
                $timeLeft = str_replace('Ds', 'D', $timeLeft);
            }
            if($hours == 1 || $hour_only == 1){
                $timeLeft = str_replace('Hours', 'Hour', $timeLeft);
                $timeLeft = str_replace('Hs', 'H', $timeLeft);
            }
            if($minutes == 1 || $min_only == 1){
                $timeLeft = str_replace('Minutes', 'Minute', $timeLeft);
                $timeLeft = str_replace('Mins', 'Min', $timeLeft);
                $timeLeft = str_replace('Ms', 'M', $timeLeft);           
            }
               
          return $timeLeft;
        }
    }
?>

php/hotblocks/nl (25-Feb-2011 10:40)

The easiest way to get the gmtime is to use gmdate():

<?php
$gmtime = (int)gmdate('U');
?>

Yi (23-Feb-2011 04:29)

A method return GMT time (gmttime):

<?php
$gmtimenow = time() - (int)substr(date('O'),0,3)*60*60;
echo $gmtimenow . "\n";
?>

it convert current time to GMT based on time zone offset.

by frank.

karls_post at hotmail dot com (23-Jan-2011 11:44)

To accurately calculate the difference between the current time and a time in the future I use the following.

<?php
function time_difference($endtime){
    $days= (date("j",$endtime)-1);
    $months =(date("n",$endtime)-1);
    $years =(date("Y",$endtime)-1970);
    $hours =date("G",$endtime);
    $mins =date("i",$endtime);
    $secs =date("s",$endtime);
    $diff="'day': ".$days.",'month': ".$months.",'year': ".$years.",'hour': ".$hours.",'min': ".$mins.",'sec': ".$secs;
    return $diff;
}   
$end_time = $future_date - time();
$difference = time_difference($end_time);
echo $difference;

//sample output
'day': 2,'month': 1,'year': 0,'hour': 2,'min': 05,'sec': 41

?>

Timo K (02-Oct-2010 01:49)

The documentation should have this info. The function time() returns always timestamp that is timezone independent (=UTC).

<?php
date_default_timezone_set("UTC");
echo "UTC:".time();
echo "<br>";

date_default_timezone_set("Europe/Helsinki");
echo "Europe/Helsinki:".time();
echo "<br>";
?>

Local time as string can be get by strftime() and local timestamp (if ever needed) by mktime().

johan dot lindskog at humlab dot umu dot se (26-Aug-2010 02:35)

I needed to convert between Unix timestamps and Windows/AD timestamps, so I wrote a pair of simple functions for it.

<?php
function unix_time_to_win_time($unix_time) {
  //add the seconds between 1601-01-01 and 1970-01-01 and make it 100-nanosecond precision
  $win_time = ($unix_time + 11644477200) * 10000000;
  return $win_time;
}

function win_time_to_unix_time($win_time) {
  //round the win timestamp down to seconds and remove the seconds between 1601-01-01 and 1970-01-01
  $unix_time = round($win_time / 10000000) - 11644477200;
  return $unix_time;
}
?>

John Galt (14-Aug-2010 11:46)

This is another function to calculate the difference between two times and output it in a relative format. This one, however, combines various units. In other words, it will return "3 days, 2 hours, 6 minutes, and 2 seconds ago" instead of "3 days ago."

Please bear in mind that it is intended for times that are very close together. It will not be accurate for calculating dates more than a month apart. This is because one of the units it relies on is "weeks," which do not correspond directly with months. What I'm trying to get across is, the program assumes that a month is precisely 4 weeks long, i.e. 28 days. This also means that a "year" according to this function is 336 days.

<?php
 function rel_time($from, $to = null)
 {
  $to = (($to === null) ? (time()) : ($to));
  $to = ((is_int($to)) ? ($to) : (strtotime($to)));
  $from = ((is_int($from)) ? ($from) : (strtotime($from)));

  $units = array
  (
   "year"   => 29030400, // seconds in a year   (12 months)
   "month"  => 2419200,  // seconds in a month  (4 weeks)
   "week"   => 604800,   // seconds in a week   (7 days)
   "day"    => 86400,    // seconds in a day    (24 hours)
   "hour"   => 3600,     // seconds in an hour  (60 minutes)
   "minute" => 60,       // seconds in a minute (60 seconds)
   "second" => 1         // 1 second
  );

  $diff = abs($from - $to);
  $suffix = (($from > $to) ? ("from now") : ("ago"));

  foreach($units as $unit => $mult)
   if($diff >= $mult)
   {
    $and = (($mult != 1) ? ("") : ("and "));
    $output .= ", ".$and.intval($diff / $mult)." ".$unit.((intval($diff / $mult) == 1) ? ("") : ("s"));
    $diff -= intval($diff / $mult) * $mult;
   }
  $output .= " ".$suffix;
  $output = substr($output, strlen(", "));

  return $output;
 }
?>

The function rel_time() accepts two parameters: $from and $to. For best results, provide them as UNIX timestamps (derived from PHP's time() function). They also accept formats supported by strtotime(). $to is an optional argument and defaults to the current time.

The function will calculate the difference between $from and $to. If $from occurs after $to, the function will substitue "ago" with "from now."

Example usage:
<?php
 echo rel_time("September 2, 2010 4:20 PM");
 // returns "2 weeks, 4 days, 23 hours, 25 minutes, and 3 seconds from now"
?>

alex nyoc net (24-Feb-2010 12:39)

Here is a really simple hack used to calculate time difference between present and past and future (in a really efficient way!)

To change between past, present, future, you need to do things only on the display side (no code patch needed).

The default function is:
<?php
timeago($referencedate=0, $timepointer='', $measureby='', $autotext=true)
?>

$timepointer is from where to start calculating and is only needed if you are calculating the difference between 2 specific times. In other words, the present is not one of those times.

$referencedate is the time you're calculating to. This is required for all calculations.

$measureby is the unit to use

$autotext is whether to add "days from now" or "ago" to the string. Option only for present dates, otherwise, this variable is set to off.

For a standard present-past, use: timeago(pastdate);

It will automatically detect the time since in the appropriate units.

There is some coding error because rounding plays a huge roll. If it's 390 days from now, instead of saying "1 year, 25 days", the function will say "1 year". Post a better solution if you can.

<?php
## alex at nyoc dot net
## Feel free to better for your needs

function timeago($referencedate=0, $timepointer='', $measureby='', $autotext=true){    ## Measureby can be: s, m, h, d, or y
    if($timepointer == '') $timepointer = time();
    $Raw = $timepointer-$referencedate;    ## Raw time difference
    $Clean = abs($Raw);
    $calcNum = array(array('s', 60), array('m', 60*60), array('h', 60*60*60), array('d', 60*60*60*24), array('y', 60*60*60*24*365));    ## Used for calculating
    $calc = array('s' => array(1, 'second'), 'm' => array(60, 'minute'), 'h' => array(60*60, 'hour'), 'd' => array(60*60*24, 'day'), 'y' => array(60*60*24*365, 'year'));    ## Used for units and determining actual differences per unit (there probably is a more efficient way to do this)
   
    if($measureby == ''){    ## Only use if nothing is referenced in the function parameters
        $usemeasure = 's';    ## Default unit
   
        for($i=0; $i<count($calcNum); $i++){    ## Loop through calcNum until we find a low enough unit
            if($Clean <= $calcNum[$i][1]){        ## Checks to see if the Raw is less than the unit, uses calcNum b/c system is based on seconds being 60
                $usemeasure = $calcNum[$i][0];    ## The if statement okayed the proposed unit, we will use this friendly key to output the time left
                $i = count($calcNum);            ## Skip all other units by maxing out the current loop position
            }       
        }
    }else{
        $usemeasure = $measureby;                ## Used if a unit is provided
    }
   
    $datedifference = floor($Clean/$calc[$usemeasure][0]);    ## Rounded date difference
   
    if($autotext==true && ($timepointer==time())){
        if($Raw < 0){
            $prospect = ' from now';
        }else{
            $prospect = ' ago';
        }
    }
   
    if($referencedate != 0){        ## Check to make sure a date in the past was supplied
        if($datedifference == 1){    ## Checks for grammar (plural/singular)
            return $datedifference . ' ' . $calc[$usemeasure][1] . ' ' . $prospect;
        }else{
            return $datedifference . ' ' . $calc[$usemeasure][1] . 's ' . $prospect;
        }
    }else{
        return 'No input time referenced.';
    }
}
?>

nickr at visuality dot com (08-Feb-2010 09:54)

Here is a version for the difference code that displays "ago" code.

It does use some precision after the time difference is longer than a day. ( ie days are more than 60 * 60 * 24 hours long )

<?php

    function ago($datefrom,$dateto=-1)
    {
        // Defaults and assume if 0 is passed in that
        // its an error rather than the epoch
   
        if($datefrom==0) { return "A long time ago"; }
        if($dateto==-1) { $dateto = time(); }
       
        // Make the entered date into Unix timestamp from MySQL datetime field

        $datefrom = strtotime($datefrom);
   
        // Calculate the difference in seconds betweeen
        // the two timestamps

        $difference = $dateto - $datefrom;

        // Based on the interval, determine the
        // number of units between the two dates
        // From this point on, you would be hard
        // pushed telling the difference between
        // this function and DateDiff. If the $datediff
        // returned is 1, be sure to return the singular
        // of the unit, e.g. 'day' rather 'days'
   
        switch(true)
        {
            // If difference is less than 60 seconds,
            // seconds is a good interval of choice
            case(strtotime('-1 min', $dateto) < $datefrom):
                $datediff = $difference;
                $res = ($datediff==1) ? $datediff.' second ago' : $datediff.' seconds ago';
                break;
            // If difference is between 60 seconds and
            // 60 minutes, minutes is a good interval
            case(strtotime('-1 hour', $dateto) < $datefrom):
                $datediff = floor($difference / 60);
                $res = ($datediff==1) ? $datediff.' minute ago' : $datediff.' minutes ago';
                break;
            // If difference is between 1 hour and 24 hours
            // hours is a good interval
            case(strtotime('-1 day', $dateto) < $datefrom):
                $datediff = floor($difference / 60 / 60);
                $res = ($datediff==1) ? $datediff.' hour ago' : $datediff.' hours ago';
                break;
            // If difference is between 1 day and 7 days
            // days is a good interval               
            case(strtotime('-1 week', $dateto) < $datefrom):
                $day_difference = 1;
                while (strtotime('-'.$day_difference.' day', $dateto) >= $datefrom)
                {
                    $day_difference++;
                }
               
                $datediff = $day_difference;
                $res = ($datediff==1) ? 'yesterday' : $datediff.' days ago';
                break;
            // If difference is between 1 week and 30 days
            // weeks is a good interval           
            case(strtotime('-1 month', $dateto) < $datefrom):
                $week_difference = 1;
                while (strtotime('-'.$week_difference.' week', $dateto) >= $datefrom)
                {
                    $week_difference++;
                }
               
                $datediff = $week_difference;
                $res = ($datediff==1) ? 'last week' : $datediff.' weeks ago';
                break;           
            // If difference is between 30 days and 365 days
            // months is a good interval, again, the same thing
            // applies, if the 29th February happens to exist
            // between your 2 dates, the function will return
            // the 'incorrect' value for a day
            case(strtotime('-1 year', $dateto) < $datefrom):
                $months_difference = 1;
                while (strtotime('-'.$months_difference.' month', $dateto) >= $datefrom)
                {
                    $months_difference++;
                }
               
                $datediff = $months_difference;
                $res = ($datediff==1) ? $datediff.' month ago' : $datediff.' months ago';

                break;
            // If difference is greater than or equal to 365
            // days, return year. This will be incorrect if
            // for example, you call the function on the 28th April
            // 2008 passing in 29th April 2007. It will return
            // 1 year ago when in actual fact (yawn!) not quite
            // a year has gone by
            case(strtotime('-1 year', $dateto) >= $datefrom):
                $year_difference = 1;
                while (strtotime('-'.$year_difference.' year', $dateto) >= $datefrom)
                {
                    $year_difference++;
                }
               
                $datediff = $year_difference;
                $res = ($datediff==1) ? $datediff.' year ago' : $datediff.' years ago';
                break;
               
        }
        return $res;

?>

andypsv at rcdrugs dot com (30-Jun-2009 07:43)

RETURNS time left from supplied date ex. '3 days ago' etc. Basic function

<?php

function _ago($tm,$rcs = 0) {
    $cur_tm = time(); $dif = $cur_tm-$tm;
    $pds = array('second','minute','hour','day','week','month','year','decade');
    $lngh = array(1,60,3600,86400,604800,2630880,31570560,315705600);
    for($v = sizeof($lngh)-1; ($v >= 0)&&(($no = $dif/$lngh[$v])<=1); $v--); if($v < 0) $v = 0; $_tm = $cur_tm-($dif%$lngh[$v]);
   
    $no = floor($no); if($no <> 1) $pds[$v] .='s'; $x=sprintf("%d %s ",$no,$pds[$v]);
    if(($rcs == 1)&&($v >= 1)&&(($cur_tm-$_tm) > 0)) $x .= time_ago($_tm);
    return $x;
}

?>

yasmary at gmail dot com (06-Mar-2009 08:48)

A time difference function that outputs the time passed in facebook's style: 1 day ago, or 4 months ago. I took andrew dot macrobert at gmail dot com function and tweaked it a bit. On a strict enviroment it was throwing errors, plus I needed it to calculate the difference in time between a past date and a future date.

<?php
function nicetime($date)
{
    if(empty($date)) {
        return "No date provided";
    }
   
    $periods         = array("second", "minute", "hour", "day", "week", "month", "year", "decade");
    $lengths         = array("60","60","24","7","4.35","12","10");
   
    $now             = time();
    $unix_date         = strtotime($date);
   
       // check validity of date
    if(empty($unix_date)) {   
        return "Bad date";
    }

    // is it future date or past date
    if($now > $unix_date) {   
        $difference     = $now - $unix_date;
        $tense         = "ago";
       
    } else {
        $difference     = $unix_date - $now;
        $tense         = "from now";
    }
   
    for($j = 0; $difference >= $lengths[$j] && $j < count($lengths)-1; $j++) {
        $difference /= $lengths[$j];
    }
   
    $difference = round($difference);
   
    if($difference != 1) {
        $periods[$j].= "s";
    }
   
    return "$difference $periods[$j] {$tense}";
}

$date = "2009-03-04 17:45";
$result = nicetime($date); // 2 days ago

?>

anon (27-Jan-2009 01:16)

Below, a function to create TNG-style stardates, taking 2009 to start stardate 41000.0.  In fact, the offset is trivial to adjust if you wish to begin from a different date.

<?php
function getStardate(void)
{
  $offset = 2000;
  $seconds_per_stardate = 31449.6; // is the number of seconds in a year divided by 1000, for hopefully obvious reasons
  return time() / $seconds_per_stardate + $offset;
}
?>

Other series use less reliable stardate formats, which makes it difficult [read: nigh impossible] to create a function that converts a unix timestamp into a stardate.

Anonymous (02-Sep-2008 01:30)

A cleaner example (half the comparisons) of distanceOfTimeInWords() function below:

<?php
public static function distanceOfTimeInWords($fromTime, $toTime = 0, $showLessThanAMinute = false) {
    $distanceInSeconds = round(abs($toTime - $fromTime));
    $distanceInMinutes = round($distanceInSeconds / 60);
       
        if ( $distanceInMinutes <= 1 ) {
            if ( !$showLessThanAMinute ) {
                return ($distanceInMinutes == 0) ? 'less than a minute' : '1 minute';
            } else {
                if ( $distanceInSeconds < 5 ) {
                    return 'less than 5 seconds';
                }
                if ( $distanceInSeconds < 10 ) {
                    return 'less than 10 seconds';
                }
                if ( $distanceInSeconds < 20 ) {
                    return 'less than 20 seconds';
                }
                if ( $distanceInSeconds < 40 ) {
                    return 'about half a minute';
                }
                if ( $distanceInSeconds < 60 ) {
                    return 'less than a minute';
                }
               
                return '1 minute';
            }
        }
        if ( $distanceInMinutes < 45 ) {
            return $distanceInMinutes . ' minutes';
        }
        if ( $distanceInMinutes < 90 ) {
            return 'about 1 hour';
        }
        if ( $distanceInMinutes < 1440 ) {
            return 'about ' . round(floatval($distanceInMinutes) / 60.0) . ' hours';
        }
        if ( $distanceInMinutes < 2880 ) {
            return '1 day';
        }
        if ( $distanceInMinutes < 43200 ) {
            return 'about ' . round(floatval($distanceInMinutes) / 1440) . ' days';
        }
        if ( $distanceInMinutes < 86400 ) {
            return 'about 1 month';
        }
        if ( $distanceInMinutes < 525600 ) {
            return round(floatval($distanceInMinutes) / 43200) . ' months';
        }
        if ( $distanceInMinutes < 1051199 ) {
            return 'about 1 year';
        }
       
        return 'over ' . round(floatval($distanceInMinutes) / 525600) . ' years';
}
?>

Josh Abraham (28-Sep-2007 03:43)

When dealing with the results of the time function, taking the modulus (remainder) is often a good way to find recurring information such as day of the week, week of the year, or month of the year. In the example given below of a firefighter's shift, you could do the following to simplify the code.

<?php

function whatShift() {

  $referencePoint = mktime(7, 0, 0, 9, 11, 2004);   // Sept 11, 2004 at 7AM started an A Shift.

  //This is the where we divide the current time since reference by the amount of time in all shifts
  //The result of this is the remainder.
  $sinceReference = (time() - $referencePoint) % (60 * 60 * 24 * 3);

  //The rest of the code can be basically the same so I shortened it here.
  if ($sinceReference < 60 * 60 * 25)  $shift = "A";
  elseif ($sinceReference < 60 * 60 * 49)  $shift = "B";
  else $shift = "C"; 

  return $shift;

}

?>

jon at freilich dot com (21-Sep-2007 05:30)

Fire Fighters typically work one day on and two days off.  Known as shifts and generally referred to as A, B and C.  I need to compute this for a web script so I came up with the following function.

Notes: You may need to change the reference date as not all departments are on the same rotation. Also, this does not take into account daylight savings time so the changeover moves by an hour.

<?php

function whatShift() {

  $referencePoint = mktime(7, 0, 0, 9, 11, 2004);   // Sept 11, 2004 at 7AM started an A Shift.
  $now = time();
 
  // Next we need to know how many seconds since the start of the last A Shift.
  // First we compute how many 3 days cycles since the reference point then
  // subtract that number.
 
  $difference = ($now - $referencePoint);
  $cycles = floor($difference / (60 * 60 * 24 * 3));
  $sinceReference = ($difference - ($cycles * 60 * 60 * 24 * 3));

  if ($sinceReference < 60 * 60 * 25) {  // Before the start of the 25th hour it's A Shift.
    $shift = "A";
    }
 
  elseif ($sinceReference < 60 * 60 * 49) {  // Else before the start of the 49th hour it's B Shift.
    $shift = "B";
    }
 
  else {
    $shift = "C";  // Else it's C Shift.
    }

  return $shift;

}

?>

by225 at yahoo dot com (06-Sep-2007 08:32)

A function for converting to Unix time without using the MySQL UNIX_TIMESTAMP function in a query (MySQL allows eight different formats for timestamps):

<?php
function UnixTime($mysql_timestamp){
    if (preg_match('/(\d{4})(\d{2})(\d{2})(\d{2})(\d{2})(\d{2})/', $mysql_timestamp, $pieces)
        || preg_match('/(\d{2})(\d{2})(\d{2})(\d{2})(\d{2})(\d{2})/', $mysql_timestamp, $pieces)) {
            $unix_time = mktime($pieces[4], $pieces[5], $pieces[6], $pieces[2], $pieces[3], $pieces[1]);
    } elseif (preg_match('/\d{4}\-\d{2}\-\d{2} \d{2}:\d{2}:\d{2}/', $mysql_timestamp)
        || preg_match('/\d{2}\-\d{2}\-\d{2} \d{2}:\d{2}:\d{2}/', $mysql_timestamp)
        || preg_match('/\d{4}\-\d{2}\-\d{2}/', $mysql_timestamp)
        || preg_match('/\d{2}\-\d{2}\-\d{2}/', $mysql_timestamp)) {
            $unix_time = strtotime($mysql_timestamp);
    } elseif (preg_match('/(\d{4})(\d{2})(\d{2})/', $mysql_timestamp, $pieces)
        || preg_match('/(\d{2})(\d{2})(\d{2})/', $mysql_timestamp, $pieces)) {
            $unix_time = mktime(0, 0, 0, $pieces[2], $pieces[3], $pieces[1]);
    }
  return $unix_time;
}
?>

lsd25 at hotmail dot com (01-Sep-2007 03:53)

I did an article on floating point time you can download from my website. Roun movements is the radial ounion movement and there is a quantum ounion movement as well, this code will generate the data for http://www.chronolabs.org.au/bin/roun-time-article.pdf which is an article on floating point time, I have created the calendar system as well for this time. It is compatible with other time and other solar systems with different revolutions of the planets as well as different quantumy stuff.

Thanks:

<?php
if ($gmt>0){
        $gmt=-$gmt;
    } else {
        $gmt=$gmt+$gmt+$gmt;
    }
   
    $ptime = strtotime('2008-05-11 10:05 AM')+(60*60*gmt);
    $weight = -20.22222222223+(1*gmt);

    $roun_xa = ($tme)/(24*60*60);
    $roun_ya = $ptime/(24*60*60);
    $roun = (($roun_xa -$roun_ya) - $weight)+(microtime/999999);
   
    $nonedeficient = array("seq1" => array(31,30,31,30,30,30,31,30,31,30,31,30),
                           "seq2" => array(31,30,31,30,31,30,31,30,31,30,31,30),   
                           "seq3" => array(31,30,31,30,30,30,31,30,31,30,31,30),
                           "seq4" => array(31,30,31,30,30,30,31,30,31,30,31,30));

    $deficient =     array("seq1" => array(31,30,31,30,30,30,31,30,31,30,31,30),
                           "seq2" => array(31,30,31,30,31,30,31,30,31,30,31,30),   
                           "seq3" => array(31,30,31,30,31,30,31,30,30,30,31,30),
                           "seq4" => array(30,30,31,30,31,30,31,30,31,30,31,30));

    $monthusage = isset($_GET['deficienty']) ? ${$_GET['deficienty']} : $deficient;
   
    foreach($monthusage as $key => $item){
        $i++;
        foreach($item as $numdays){
            $ttl_num=$ttl_num+$numdays;
        }
    }
   
    $revolutionsperyear = $ttl_num / $i;
    $numyears = round((round(ceil($roun)) / $revolutionsperyear),0);
   
    $jtl = abs(abs($roun) - ceil($revolutionsperyear*($numyears+1)));
   
    while($month==0){
        $day=0;
        foreach($monthusage as $key => $item){
            $t++;
            $u=0;
            foreach($item as $numdays){
                if ($ii<abs($roun)){
                    $isbelow=true;
                }
                $ii=$ii+$numdays;
                if ($ii>abs($roun)){
                    $isabove=true;
                }
                if ($isbelow==true&&$isabove==true){
                    $daynum = floor(($ii-$numday)-abs($roun));
                    $month = $u;
                    $month++;
                    $isbelow=false;
                    $isabove=false;
                    $nodaycount=true;
                }
                if ($nodaycount==false)
                    $day++;
                $u++;
            }
        }
   
    }
   
    $timer = substr($roun, strpos($roun,'.')+1,strlen($roun)-strpos($roun,'.')-1);
   
    $roun_out= $numyears.'-'.$month.'-'.$daynum.' '.$day.".$timer";

?>

send at mail dot 2aj dot net (08-Jun-2006 07:58)

If you want to create a "rounded" time stamp, for example, to the nearest 15 minutes use this as a reference:

<?php
$round_numerator = 60 * 15 // 60 seconds per minute * 15 minutes equals 900 seconds
//$round_numerator = 60 * 60 or to the nearest hour
//$round_numerator = 60 * 60 * 24 or to the nearest day

// Calculate time to nearest 15 minutes!
$rounded_time = ( round ( time() / $round_numerator ) * $round_numerator );

//If it was 12:40 this would return the timestamp for 12:45;
//3:04, 3:00; etc.
?>

aidan at php dot net (08-Oct-2005 01:14)

A simple function for calculating the number of seconds, minutes, etc in a timestamp is here:
http://aidanlister.com/2004/04/making-time-periods-readable/

Example:
<?php
echo time_duration(100000000);
// 3 years, 2 months, 19 hours, 22 minutes, 16 seconds

echo time_duration(100000000, null, true);
// 3 years, 2 months, 0 weeks, 0 days, 19 hours, 22 minutes, 16 seconds

echo time_duration(100000000, 'yMw');
// 3 years, 2 months

echo time_duration(100000000, 'd');
// 1157 days
?>


It is also worth noting:
* For manipulating arbitrary format, or length timestamps, see the PEAR::Date class.
http://pear.php.net/package/Date/
* PHP 6 will be shipping a new inbuilt date and timestamp manipulation API. It's available on PECL here:
http://pecl.php.net/package/datetime

mayank_arya at hotmail dot com (29-May-2003 02:13)

Here's one way to generate all intermediate dates (in mySQL format) between any 2 dates.
Get start and end dates from user input, you'd need to do the basic validations that :
- start and end dates are valid dates
- start date <= end date.

<?php
//start date 2001-02-23
$sm=2;
$sd=23;
$sy=2001;

//end date 2001-03-14
$em=3;
$ed=14;
$ey=2001;

//utc of start and end dates
$s=mktime(0,0,0,$sm, $sd, $sy);
$e=mktime(0,0,0,$em, $ed, $ey);

while($s<=$e){
print date('Y-m-d',$s)."< br >"; //display date in  mySQL format
$s=$s+86400; //increment date by 86400 seconds(1 day)
}

Hope this helps :)

?>