验证开始日期和结束日期之间的PHP

Question

I am trying to validate input date fields, and I want to make sure that the entires are no more than 90 days difference from each other. Could anyone offer any solutions to the function I need to be using here. Below is my psuedocode of what I want to achieve.

if (($filter_in['dt']-90) > ($filter_in['df']));

The -90 bit is where I need to minus 90 days from the end date. Is it possible to go about this in this approach?

Answer 1

Do like this

<?php
$datetime1 = new DateTime('2012-10-11');
$datetime2 = new DateTime('2012-09-13');
$interval = $datetime2->diff($datetime1);
$diff= $interval->format('%R%a');
if($diff=="+90"){
   //your code
}
?> 

or in above code you can just format like this

$diff= $interval->format('%a');

or simply like @vascowhite said

$diff= $interval->days;

to get a positive integer only, the above code returns 28 which is in days.