PHP - 以秒为单位获取两个日期时间之间的差异

PHP - Get difference between two datetime in seconds

我有一个日期时间值,我现在想要那个日期时间和日期时间之间的差值。我试图将它转换为时间戳并计算差值,但我得到了一个负值。如何获得秒数差异?

<?php 
$datetimenow = strtotime(date("Y/m/d H:i:s"));
$mydatetime = strtotime(date('2015/10/09 14:20:00'));
echo ($datetimenow - $mydatetime);
?>

改用DateTime class,即:

date_default_timezone_set( 'Europe/Lisbon' ); //set your desired timezone
$now = new DateTime( 'NOW' );
$future = new DateTime( '2015/10/09 15:20:00' );
$diffSeconds = $future->getTimestamp() - $now->getTimestamp();
# 2220

我喜欢 Carbon 库...https://github.com/briannesbitt/Carbon

$diff = Carbon::now()->diffInSeconds(Carbon::parse('2015/10/09 14:20:00'));