Pass value when form submitted to If function on another file - php

Question

I have two different files.
Checkoutstep4.php
Checkoutstep5.php
When the first form is submitted, I want to take the value of 'country' which has been submitted and use it in an IF function:
This is what I have so far using session variable...
however I get an error saying undefined index and I am not sure why.
checkoutDeliveryInfo (file that runs when the delivery details form is submitted).
<?php
session_start();
require_once 'DatabaseConnection.php';
$_SESSION['customerid'];
if (isset($_POST['submit'])) {
$stmt = $pdo->prepare("INSERT INTO DeliveryDetails (customerid,firstname,lastname, addressline1, addressline2, city, county, country, postalcode)
VALUES ({$_SESSION['customerid']}, :firstname, :lastname, :addressline1, :addressline2, :city, :county, :country, :postalcode)");
$stmt->bindParam(':firstname', $firstname);
$stmt->bindParam(':lastname', $lastname);
$stmt->bindParam(':addressline1', $addressline1);
$stmt->bindParam(':addressline2', $addressline2);
$stmt->bindParam(':city', $city);
$stmt->bindParam(':county', $county);
$stmt->bindParam(':country', $country);
$stmt->bindParam(':postalcode', $postalcode);
$firstname = $_POST['firstname'];
$lastname = $_POST['lastname'];
$addressline1 = $_POST['addressline1'];
$addressline2 = $_POST['addressline2'];
$city = $_POST['city'];
$county = $_POST['county'];
$country = $_POST['country'];
$postalcode = $_POST['postalcode'];
$stmt->execute();
$_SESSION['country'] = $country;
header('location:../View/php_shopping_cart/CheckoutStep5.php');
}
IF function in the Checkoutstep5.php file where the session variable is being used:
<?php
include '../../Model/ShoppingCart.php';
$shoppingCart = new ShoppingCart;
// redirect to home if cart is empty
if ($shoppingCart->total_items() <= 0) {
header("Location: ../index.php");
}
?>
<div class="shippingcost"><strong>Shipping Cost <?php
if ($_SESSION['country'] != 'GIB') {
$shippingcost = '10.00';
} else {
$shippingcost = 'FREE';
}
echo $shippingcost;
?></strong>
</div>
Any help is appreciated.
Update: Error Message:
Notice: Undefined index: country in /home/k1509759/www/barbarycoast/View/php_shopping_cart/CheckoutStep5.php on line 246

Answer 1

I've managed to do it by extracting all variables from the session and then using the individual one i wanted.
extract($_SESSION);
if ($country == 'GIB') {
$shippingcost = 'FREE';
} else if ($country == 'GBR') {
$shippingcost = '£10.00';
} else if ($country == 'ESP') {
$shippingcost = '£10.00';
}