Date Of Birth Form

[Sharif]

What would be the best way of creating form fields to collect a person's date of birth?

I was thinking of having three form fields, one for month, day, and year.

If I gave them each a variable like: $m, $d, $y, I could then add them together with $dob = "$y-$m-$d" because I'd have to insert it into a database.

But then, how would I check to see if a person is under 18? I want the age limit to be 18 and up.

[LordShryku]

Okay, sounds like you got the form down. Here's some code to calculate age. Just wrote it, might not actually work 😃

<?
//So lets assume the date they enter is July 4th, 1987
$dob = $_POST['Year']."-".$_POST['Month']."-".$_POST['Day'];
// should return $dob = "1987-07-04";
$ageDif = (time() - strtotime($dob)); //create time from input form fields
$howOld = ($ageDif/31536000); //31536000 seconds in a year
if($howOld < 21) {
    echo "You are too young(".number_format($howOld)." years old)";
}
else {
    echo "You are old enough";
}
?>

[Sharif]

So this would display a error message to a person that isn't 18?

[LordShryku]

I used 21 as the example, just change this line

if($howOld < 21) {

to 18, and yeah, it would display an error message

[Sharif]

Ah ok, thanks a lot. Can you please explain to me the two variables... I want to know how it works 🙂.

[LordShryku]

Well damn, I even put comments in that one, but here goes again.

$dob is putting together the sting from your form fields to make a date string like yyyy-mm-dd

$ageDif is subtracting the current timestamp against the $dob timestamp

$howOld calculates the age in years of the person.

You should look up these functions in the manual. All are pretty common and straight forward