Discount Code for Members of Certain Levels Only

pmpro-discount-code-for-membersonly.php

<?php   // do not copy this line.
/**
 * Restrict discount code usage to members of certain levels
 * 
 * You can add this recipe to your site by creating a custom plugin
 * or using the Code Snippets plugin available for free in the WordPress repository.
 * Read this companion article for step-by-step directions on either method.
 * https://www.paidmembershipspro.com/create-a-plugin-for-pmpro-customizations/
 */

function my_pmpro_check_discount_code($okay, $dbcode, $level_id, $code) {

	// membership levels allowed to use discount codes below
	$code_levels = array( 1, 2 );

	// member only codes, in UPPERCASE
	$member_codes = array( 'YOURCODEHERE' );
	
	if ( in_array( strtoupper( $code ), $member_codes ) && ! pmpro_hasMembershipLevel( $code_levels ) ) {
		return 'You must be a member of level 1 or level 2 to use that discount code.'; // your error message
	}
	return $okay;
}
add_filter( 'pmpro_check_discount_code', 'my_pmpro_check_discount_code', 10, 4 );