The fullstripe_billing_countries Wordpress filter

fullstripe_billing_countries_v6-1.php

<?php
/**
 * A 'fullstripe_billing_countries' filter hook example for WP Full Stripe.
 * It sets Spain as the only country offered in billing country dropdown on all forms.
 *
 * @param string $countryCodes Array of 2-letter ISO country codes returned by previous filters of the chain.
 * @param array $params with the following keys:
 *   formName               => Name of the form that requires the list of billing countries. 
 *   formType               => Type of the form that requires the list of billing countries. Possible values:
 *                             inline_payment
 *                             checkout_payment
 *                             inline_subscription
 *                             checkout_subscription
 *                             inline_donation
 *                             checkout_donation
 *                             inline_save_card
 *                             checkout_save_card
 *
 * @return string Filtered array of 2-letter ISO country codes
 */
function getBillingCountries( $countryCodes, $params) {
    $result = $countryCodes;
    
    // Set Spain as the only billing country for every form
    $result = [ 'ES' ]; 

    return $result;
}

add_filter('fullstripe_billing_countries', 'getBillingCountries', 10, 2 );