Hide top admin panel for non admin and non editors

Question

This is what i am using;

add_action('init', 'blockusers_init');

function blockusers_init() {
    if (is_admin() && !current_user_can('administrator') &&
        !(defined('DOING_AJAX') && DOING_AJAX)) {
        wp_redirect(home_url());
        exit;
    }
}

It’s possible the best one.

EDIT : You need a custom login page for reach wp-admin. This code redirect to homepage if you enter directly to wp-admin.