This tips suppose that you already installed a plugin to add new fields in the user profile.
So now let suppose (again) that you added the 3 fields for the birth date : month, day and year.
So now if you want to display the age of the author resulting from this date in the author page :
Paste after <?php get_header(); ?> in author.php :
`<?php function birthday ($birthday) {
list($year,$month,$day) = explode("-",$birthday);
$year_diff = date("Y") - $year;
$month_diff = date("m") - $month;
$day_diff = date("d") - $day;
if ($month_diff < 0) $year_diff--;
elseif (($month_diff==0) && ($day_diff < 0)) $year_diff--;
return $year_diff;
}
?>`
And then where you want to display the age :
Age : <?php echo birthday("$curauth->birth_year;-$curauth->birth_month;-$curauth->birth_day;");?>
(N.B : birth_year, birth_month, birth_day) are the name of the usermeta and fields in your user profile)
