PHP - 如何从DateTime对象获取日期时间字符串

I've made a DateTime object using

$currtime = DateTime::createFromFormat("YmdHi");

Is there a way to get a string or an integer, which contains, for example, 201604041825?

$currtime->modify("+2 hours");
$newtime = $currtime->format("YmdHi");

returned

$newtime = 2147483647

This will help you

$current_date_object= new DateTime();
$current_date_object->modify("+2 hours");
$current_date_string= $current_date_object->format("Y-m-d H:i:sO");