php pdo ไม่แสดงผลออก Browser ทำไงให้มันออกครับ ช่วยดูหน่อยครับ

    $db_con = 'mysql:host = localhost;dbname = db_school_tpd';
    $username = 'root';
    $password = '';

    try {
        $conn = new PDO($db_con,$username,$password);
        $conn -> exec("set names utf8");
        $conn -> setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE, PDO::ERRMODE_EXCEPTION);
    } catch (Exception $e) {
        echo $e->getMessage();
    }
   $stm = $conn->prepare("SELECT * FROM s_sex");
$stm->execute();
$resultarray=$stm->fetchAll();

$conn=null;

count($resultarray);

for ($i=0; $i < count($resultarray) ; $i++) {
  echo ".$resultarray[$i]['s_SexID'].";
}