php - comparing timestamp dates to make sure user is of minimum age

Question

Possible Duplicate:
How to calculate the difference between two dates using PHP?

When a user signs up the system has to check that they are old enough to do so, in this example they have to be atleast 8 years old

$minAge = strtotime(date("d")."-".date("m")."-".(date("Y")-8));
$dob = strtotime($day."-".$month."-".$year);

$minAge = 01-03-2004, $dob = 01-02-2011

I basically need to make sure this person was born before 2004 but I want to know whether I have to convert the timestamps to do a comparison or whether there is a more efficient way.

Any help is appreciated, thank you

score 0 · Accepted Answer · answered Mar 24 '12 at 17:21

0

With your $dob timestamp, you can subtract that from the current date's timestamp, and then balance those values versus your minAge. ex:

if(($dob-time())=>$minAge) {
   //OVER 8 YEARS
} else {
   //UNDER 8
}

Although, with this method you are comparing minage as a timestamp without days, hours, minutes or seconds, so keep that in mind when using the "time()" value as described in this example.

answered Mar 24 '12 at 17:21

Ben Ashton

1,385
10
15

1

Thanks this is the simplest solution, after testing it I guess it works great – Micheal Ken Mar 24 '12 at 17:33

score 0 · Answer 2 · answered Mar 24 '12 at 17:25

0

I think you just need to do something like this:

$dob = strtotime('1-1-2012');
$minAge = (60*60*24*365*8);//number of seconds of 8 years
if(time()-$dob>= $minAge)
{
   //OK

}
else
{
   //NOT OK
}

answered Mar 24 '12 at 17:25

hungneox

9,333
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Nemoden · Answer 3 · 2012-03-24T17:50:05.187

0

With PHP 5 you can use DateTime class for this kind of things:

function allowed_to_watch_adult_movies($birthday) {
  $min_age = 18;
  $user = new DateTime($birthday);
  $min_birthday = new DateTime('now - '.$min_age.' years');
  $interval = date_diff($min_birthday, $user);
  return $interval->invert == 1;
}
printf('Kid is %sallowed to watch adult movies<br />' , 
       allowed_to_watch_adult_movies('2004-05-18') ? '' : 'not ' );
printf('Grandpa is %sallowed to watch adult movies, but he does not care<br />' , 
       allowed_to_watch_adult_movies('1954-05-12') ? '' : 'not ' );

edited Mar 24 '12 at 17:50

answered Mar 24 '12 at 17:35

Nemoden

8,816
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You might want to change your function to something... else... before this gets flagged. – BoltClock Mar 24 '12 at 17:44
Why would anyone flag answer which contains working code? Or does the word "porn" offend someone? – tereško Mar 24 '12 at 17:48
Ok, ok... I did not know, we are so sensitive here - sorry. I thought it is funny, not offending. – Nemoden Mar 24 '12 at 17:50
Stack Overflow is a professional community, so yes, we are that sensitive with regards to content. Please keep that in mind. – BoltClock Mar 24 '12 at 17:52

php - comparing timestamp dates to make sure user is of minimum age

3 Answers3