- date_diff: documentation ( source)
- print_r: documentation ( source)
<?php
$a = new DateTime('2000-01-31');
$b = new DateTime('2010-06-15');
$diff = date_diff($a, $b);
echo '$a=', $a->format('Y-m-d H:i:s'), "\n";
echo '$b=', $b->format('Y-m-d H:i:s'), "\n";
print_r($diff);