Restrict email domains for newly registered users #hivepress #users

functions.php

<?php
add_filter(
	'hivepress/v1/forms/user_register/errors',
	function( $errors, $form ) {
		if ( ! $errors ) {
			$domain = hivepress()->helper->get_last_array_value( explode( '@', $form->get_value( 'email' ) ) );

			if ( ! in_array(
				$domain,
				[
					'gmail.com',
					'yahoo.com',
					'outlook.com',
				]
			) ) {
				$errors[] = 'This email domain is not allowed.';
			}
		}

		return $errors;
	},
	1000,
	2
);