根据当前日期计算年龄

<?php

function birthday($birthday){

 $age = strtotime($birthday);

 if($age === false){

  return false;

 }

 list($y1,$m1,$d1) = explode("-",date("Y-m-d",$age));

 $now = strtotime("now");

 list($y2,$m2,$d2) = explode("-",date("Y-m-d",$now));

 $age = $y2 - $y1;

 if((int)($m2.$d2) < (int)($m1.$d1))

  $age -= 1;

 return $age;

}

echo birthday(‘1986-07-22‘);

?>