How to get weeks between two dates

Question

How do I get a reliable date diff in weeks?

So far I've got

<?php
$a = new DateTime('2010-09-01');
$b = new DateTime();

$c = $a->diff($b);

Now I get a DateInterval with years, months and so on, but as far as I know a year does not have exactly 52 weeks and so doesn't a month have exactly 4 weeks.

Any suggestions how to get the real, reliable week count?

Answer 1

Maybe you can Count the days between your two dates and divide by 7?

Answer 2

get the difference in days, and divide it by 7? or, if you are using older versions of PHP, get the differences in hours/minutes/seconds, and calculate it accordingly..