Block user roles from accessing the WordPress dashboard

Question

I want to block multiple user roles from accessing the WordPress dashboard, I have a custom role, and I want to block it along with other roles, but I don't know how to edit the code.

the code below has one role (shopkeeper) I want to add more roles how can I do that?

function wpse66094_no_admin_access() {
    $redirect = isset( $_SERVER['HTTP_REFERER'] ) ? $_SERVER['HTTP_REFERER'] : home_url( '/' );
    global $current_user;
    $user_roles = $current_user->roles;
    $user_role = array_shift($user_roles);
    if($user_role === 'shopkeeper'){
        exit( wp_redirect( $redirect ) );
    }
 }

add_action( 'admin_init', 'wpse66094_no_admin_access', 100 );

Answer 1

You can make an array of the roles that need to be blocked, and use array_intersect() to check if the current user is in any of those roles.

function wpse66094_no_admin_access() {
    $redirect = isset( $_SERVER['HTTP_REFERER'] ) ? $_SERVER['HTTP_REFERER'] : home_url( '/' );
    global $current_user;
    $blocked_roles = array( 
        'shopkeeper',
        'block-this-role',
        'block-this-role-too'
    );
    $user_roles = $current_user->roles;
    // If the user is in any of the blocked roles, redirect 'em.
    if ( ! empty( array_intersect( $user_roles, $blocked_roles ) ) ) {
        wp_safe_redirect( $redirect );
        exit;
    }
 }

add_action( 'admin_init', 'wpse66094_no_admin_access', 100 );

Thanks to @Cornell Raiu in the comments for correcting the wp_redirect() / exit code, and @TomJNowell for recommending wp_safe_redirect().