$date = '2012.11.13';
$dateOfReturn = '2017.10.31';

$substract = str_replace('.', '-', $date);

$substract2 = str_replace('.', '-', $dateOfReturn);



$date1 = $substract;
$date2 = $substract2;

$ts1 = strtotime($date1);
$ts2 = strtotime($date2);

$year1 = date('Y', $ts1);
$year2 = date('Y', $ts2);

$month1 = date('m', $ts1);
$month2 = date('m', $ts2);

echo $diff = (($year2 - $year1) * 12) + ($month2 - $month1);

当PHP 5.3（分别为date_diff（））不可用时，我使用了我编写的以下函数：

        function dateDifference($startDate, $endDate)
        {
            $startDate = strtotime($startDate);
            $endDate = strtotime($endDate);
            if ($startDate === false || $startDate < 0 || $endDate === false || $endDate < 0 || $startDate > $endDate)
                return false;

            $years = date('Y', $endDate) - date('Y', $startDate);

            $endMonth = date('m', $endDate);
            $startMonth = date('m', $startDate);

            // Calculate months
            $months = $endMonth - $startMonth;
            if ($months <= 0)  {
                $months += 12;
                $years--;
            }
            if ($years < 0)
                return false;

            // Calculate the days
            $measure = ($months == 1) ? 'month' : 'months';
            $days = $endDate - strtotime('+' . $months . ' ' . $measure, $startDate);
            $days = date('z', $days);   

            return array($years, $months, $days);
        }

// If you just want to see the year difference then use this function.
// Using the logic I've created you may also create month and day difference
// which I did not provide here so you may have the efforts to use your brain.
// :)
$date1='2009-01-01';
$date2='2010-01-01';
echo getYearDifference ($date1,$date2);
function getYearDifference($date1=strtotime($date1),$date2=strtotime($date2)){
    $year = 0;
    while($date2 > $date1 = strtotime('+1 year', $date1)){
        ++$year;
    }
    return $year;
}

function showTime($time){

    $start      = strtotime($time);
    $end        = strtotime(date("Y-m-d H:i:s"));
    $minutes    = ($end - $start)/60;


    // years 
    if(($minutes / (60*24*365)) > 1){
        $years = floor($minutes/(60*24*365));
        return "From $years year( s ) ago";
    }


    // monthes 
    if(($minutes / (60*24*30)) > 1){
        $monthes = floor($minutes/(60*24*30));
        return "From $monthes monthe( s ) ago";
    }


    // days 
    if(($minutes / (60*24)) > 1){
        $days = floor($minutes/(60*24));
        return "From $days day( s ) ago";
    }

    // hours 
    if(($minutes / 60) > 1){
        $hours = floor($minutes/60);
        return "From $hours hour( s ) ago";
    }

    // minutes 
    if($minutes > 1){
        $minutes = floor($minutes);
        return "From $minutes minute( s ) ago";
    }
}

echo showTime('2022-05-05 21:33:00');

对于php版本>=5.3：创建两个日期对象，然后使用date_diff（）函数。它将返回phpDateInterval对象。请参阅文档

$date1=date_create("2007-03-24");
$date2=date_create("2009-06-26");
$diff=date_diff($date1,$date2);
echo $diff->format("%R%a days");

<?php
    $today = strtotime("2011-02-03 00:00:00");
    $myBirthDate = strtotime("1964-10-30 00:00:00");
    printf("Days since my birthday: ", ($today - $myBirthDate)/60/60/24);
?>