Subtracting Time Problem

Hi Again

i have a two time values

$to=09:00:00

$from=10:00:00

$diff= $from -$to ...........

how do i do this ..... and also i want get answer as minites

plzzzzzz help me for solve this

I'm not sure if there's an inbuilt function or something. But i'd use seconds to do the math then write a function to turn it into a string of a time format. Then there is this http://php.net/manual/en/function.strtotime.php if you want an actual time stamp....but then I always do stuff the hard way :P

if your php >= 5.3 you can use date_diff (http://php.net/manual/en/function.date-diff.php) function :)