我做了这个，它工作得很好，它既适用于Unix时间戳，如1470919932，也适用于格式化时间，如16-08-11 14:53:30

function timeAgo($time_ago) {
    $time_ago =  strtotime($time_ago) ? strtotime($time_ago) : $time_ago;
    $time  = time() - $time_ago;

switch($time):
// seconds
case $time <= 60;
return 'lessthan a minute ago';
// minutes
case $time >= 60 && $time < 3600;
return (round($time/60) == 1) ? 'a minute' : round($time/60).' minutes ago';
// hours
case $time >= 3600 && $time < 86400;
return (round($time/3600) == 1) ? 'a hour ago' : round($time/3600).' hours ago';
// days
case $time >= 86400 && $time < 604800;
return (round($time/86400) == 1) ? 'a day ago' : round($time/86400).' days ago';
// weeks
case $time >= 604800 && $time < 2600640;
return (round($time/604800) == 1) ? 'a week ago' : round($time/604800).' weeks ago';
// months
case $time >= 2600640 && $time < 31207680;
return (round($time/2600640) == 1) ? 'a month ago' : round($time/2600640).' months ago';
// years
case $time >= 31207680;
return (round($time/31207680) == 1) ? 'a year ago' : round($time/31207680).' years ago' ;

endswitch;
}

?>

我修改了原来的函数一点(在我看来更有用，或更符合逻辑)。

// display "X time" ago, $rcs is precision depth
function time_ago ($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 ($v = count($lngh) - 1; ($v >= 0) && (($no = $dif / $lngh[$v]) <= 1); $v--);
    if ($v < 0)
      $v = 0;
  $_tm = $cur_tm - ($dif % $lngh[$v]);

  $no = ($rcs ? floor($no) : round($no)); // if last denomination, round

  if ($no != 1)
    $pds[$v] .= 's';
  $x = $no . ' ' . $pds[$v];

  if (($rcs > 0) && ($v >= 1))
    $x .= ' ' . $this->time_ago($_tm, $rcs - 1);

  return $x;
}

下面是一个非常简单和非常有效的解决方案。

function timeElapsed($originalTime){

        $timeElapsed=time()-$originalTime;

        /*
          You can change the values of the following 2 variables 
          based on your opinion. For 100% accuracy, you can call
          php's cal_days_in_month() and do some additional coding
          using the values you get for each month. After all the
          coding, your final answer will be approximately equal to
          mine. That is why it is okay to simply use the average
          values below.
        */
        $averageNumbDaysPerMonth=(365.242/12);
        $averageNumbWeeksPerMonth=($averageNumbDaysPerMonth/7);

        $time1=(((($timeElapsed/60)/60)/24)/365.242);
        $time2=floor($time1);//Years
        $time3=($time1-$time2)*(365.242);
        $time4=($time3/$averageNumbDaysPerMonth);
        $time5=floor($time4);//Months
        $time6=($time4-$time5)*$averageNumbWeeksPerMonth;
        $time7=floor($time6);//Weeks
        $time8=($time6-$time7)*7;
        $time9=floor($time8);//Days
        $time10=($time8-$time9)*24;
        $time11=floor($time10);//Hours
        $time12=($time10-$time11)*60;
        $time13=floor($time12);//Minutes
        $time14=($time12-$time13)*60;
        $time15=round($time14);//Seconds

        $timeElapsed=$time2 . 'yrs ' . $time5 . 'months ' . $time7 . 
                     'weeks ' . $time9 .  'days ' . $time11 . 'hrs '
                     . $time13 . 'mins and ' . $time15 . 'secs.';

        return $timeElapsed;

}

回显时间已用（1201570814）;

样例输出:

6年4个月3周4天12小时40分36秒。

这里的许多解决方案没有考虑舍入。例如:

事件发生在两天前的下午3点。如果您在下午2点查看，它会显示在一天前。如果你在下午4点查看，它会显示两天前。

如果你使用unix时间，这有助于:

// how long since event has passed in seconds
$secs = time() - $time_ago;

// how many seconds in a day
$sec_per_day = 60*60*24;

// days elapsed
$days_elapsed = floor($secs / $sec_per_day);

// how many seconds passed today
$today_seconds = date('G')*3600 + date('i') * 60 + date('s');

// how many seconds passed in the final day calculation
$remain_seconds = $secs % $sec_per_day;

if($today_seconds < $remain_seconds)
{
    $days_elapsed++;
}

echo 'The event was '.$days_ago.' days ago.';

如果你担心闰秒和夏时制，这并不完美。

下面是我不久前构建的通知模块的解决方案。它返回的输出类似于Facebook的通知下拉列表(例如。1天前，刚才，等等)。

public function getTimeDifference($time) {
    //Let's set the current time
    $currentTime = date('Y-m-d H:i:s');
    $toTime = strtotime($currentTime);

    //And the time the notification was set
    $fromTime = strtotime($time);

    //Now calc the difference between the two
    $timeDiff = floor(abs($toTime - $fromTime) / 60);

    //Now we need find out whether or not the time difference needs to be in
    //minutes, hours, or days
    if ($timeDiff < 2) {
        $timeDiff = "Just now";
    } elseif ($timeDiff > 2 && $timeDiff < 60) {
        $timeDiff = floor(abs($timeDiff)) . " minutes ago";
    } elseif ($timeDiff > 60 && $timeDiff < 120) {
        $timeDiff = floor(abs($timeDiff / 60)) . " hour ago";
    } elseif ($timeDiff < 1440) {
        $timeDiff = floor(abs($timeDiff / 60)) . " hours ago";
    } elseif ($timeDiff > 1440 && $timeDiff < 2880) {
        $timeDiff = floor(abs($timeDiff / 1440)) . " day ago";
    } elseif ($timeDiff > 2880) {
        $timeDiff = floor(abs($timeDiff / 1440)) . " days ago";
    }

    return $timeDiff;
}

试试这个，我从我的旧代码中找到的，它显示了正确的结果

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' : $datediff . ' seconds';
            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' : $datediff . ' minutes';
            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' : $datediff . ' hours';
            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';
            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';
            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' : $datediff . ' months';

            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' : $datediff . ' years';
            break;
    }
    return $res;
}

示例:echo ago('2020-06-03 00:14:21 AM');

产出:6天