計算兩個日期之間的差異並存儲在會話中

Question

我試圖計算兩個日期之間的差異並將結果存儲在會話中，然後再使用它。問題是當我顯示結果時顯示0。這裏是我想：

$created = ('y:m:d'); // $created comes from db where the row is DATETIME  

$startTimeStamp = strtotime($created); 
$Today=date('y:m:d'); 

$timeDiff = abs($Today - $startTimeStamp); 

$numberDays = $timeDiff/86400; 

$numberDays = intval($numberDays); 

$_SESSION['created'] = $numberDays; 

Answer 1

試試這個：
$創建=（ 'Y：M：d H：I：S'）;
$ startTimeStamp = strtotime（$ created）;
$ date = date（'Y：m：d h：i：s'）;
$ Today = strtotime（$ date）;
$ timeDiff = abs（$ Today - $ startTimeStamp）;
$ numberDays = $ timeDiff/86400;
$ numberDays = intval（$ numberDays）;
$ _SESSION ['created'] = $ numberDays;

Answer 2

<?php 
    $datetime1 = new DateTime('2009-10-11'); 
    $datetime2 = new DateTime('2009-10-13'); 
    $interval = $datetime1->diff($datetime2); 
    echo $interval->format('%R%a days'); 
?>