How to get the difference between two dates with 360 days/year, 30 days/month format?

Question

I can get the difference between two dates (DD/MM/YY format) with the following code;

$date1   = new DateTime("1986-04-27");
$today  = new DateTime("now");
$interval   = $date1->diff($today);
$year       = $interval->format('%y');
$month      = $interval->format('%m');
$day        = $interval->format('%d');

It works perfect when calculating 1 year 2 months but when I'm trying to calculate 1 year 2 months 3 days, it doesn't give me the accurate result.

I would like to get the difference between two dates, using 360 days for a year, 30 days for a month, without calculating leap years..

For example; if a month has 31 days the system will calculate it as 30 days. If a year has 365 days, the system will calculate it as 1 year 5 days. (360 + 5)

How can I do that?

Thank you..

Answer 1

Here is the way to do it:

function diff360($date1, $date2) {
    $date1 = new DateTime($date1);
    $date2 = new DateTime($date2);
    $diff = $date1->diff($date2);
    $days = ($date2->format('d') + 30 - $date1->format('d')) % 30;
    return array(
        "y" => $diff->y,
        "m" => $diff->m,
        "d" => $days,
        "totaldays" => $diff->y * 360 + $diff->m * 30 + $days
    );
}

$result = diff360("2016-02-06", "2016-03-06");
var_export($result);

Output:

array (
  'y' => 0,
  'm' => 1,
  'd' => 0,
  'totaldays' => 30,
)