Validate if age is over 18 years old

Question

Just wondering, can I do this to validate that a user has entered a date over 18?

//Validate for users over 18 only
function time($then, $min)
{
    $then =          


        

Answer 1

I think it is best using the DateTime class for this.

$bday = new DateTime("22-10-1993");  
$bday->add(new DateInterval("P18Y")); //adds time interval of 18 years to bday  
//compare the added years to the current date  
if($bday < new DateTime()){   
    echo "over 18";  
}else{  
    echo "below 18";
}

DateTime::diff can also be used to compare the date with the current date.

$today = new DateTime(date("Y-m-d"));
$bday = new DateTime("22-10-1993");
$interval = $today->diff($bday);
if(intval($interval->y) > 18){
    echo "older than 18";
}else{
    echo "younger than 18";
}

N/B: 1) for the second method , if $bday is greater than $today by 18 years or more, it will return older , so make sure date entered is less than $today . 2) DateTime works on php 5.2.0 and above