<?php
global $user;
$user_fields = user_load($user->uid);
switch ($field_apartment_blk) {
    case "0":
        echo "Apartment Bock is A";
        break;
    case "1":
        echo "Apartment Bock is B";
        break;
    case "2":
        echo "Apartment Bock is C";
        break;
 case "3":
        echo "Apartment Bock is D";
        break;
}

$block = $user_fields->$field_apartment_blk['und']['0']['value'];
$no = $user_fields->field_apartment_no['und']['0']['value'];

print  t("Your Apartment No: " . $block. ' ' . $no) ;
?>