Use conditionals with wp_enqueue_style to attach stylesheet according to post type displayed

Question

I have many custom post types, including some introduced by plugin such as bbPress or WooCommerce.

My standard stylesheet is growing large, so I thought to split it into multiple stylesheets according to post types being viewed in the browser. In this way, when the users is viewing bbpress fourms, he will also load a forum.css; when viewing wordpress pages, he would load a page.css. And so on.

I tried with the following code added in my functions.php:

function sg_frontend_enqueue_styles(){

    $templateuri = get_template_directory_uri();

    // some of my custom post types
    if( get_post_type() == ( 'activity' OR 'dining' OR 'heritage' OR 'hiking' OR 'nightlife' ) ) :  
        wp_enqueue_style( 'locations', $templateuri.'/css/locations.css', '', false, 'all' );

    // bbPress forums
    elseif ( get_post_type() == ( 'forum' OR 'topic' OR 'reply' ) ) :
        wp_enqueue_style( 'forum', $templateuri.'/css/forum.css', '', false, 'all' );

    // Pages
    elseif ( get_post_type() == 'page' ) :
        wp_enqueue_style( 'page', $templateuri.'/css/page.css', '', false, 'all' );

    // WooCommerce
    elseif ( get_post_type() == 'product' ) :
        wp_enqueue_style( 'product', $templateuri.'/css/product.css', '', false, 'all' );

    endif;

add_action('wp_print_styles', 'sg_frontend_enqueue_styles');

However this is not working. Problem: all CSS styles are loaded altogether, regardless of whether the user is displaying a post belonging to that specific post type. Furthermore, 'page.css' is not being included at all.

I've then tried with a different approach, replacing conditionals with a switch:

    $templatename = get_post_type();
    switch ( $templatename ) :
        case 'activity' :
            wp_enqueue_style( 'locations', $templateuri.'/css/locations.css', '', false, 'all' );
        case 'dining' :
            wp_enqueue_style( 'locations', $templateuri.'/css/locations.css', '', false, 'all' );
        case 'forum' :
            wp_enqueue_style( 'forum', $templateuri.'/css/forum.css', '', false, 'all' );
        case 'heritage' :
            wp_enqueue_style( 'locations', $templateuri.'/css/locations.css', '', false, 'all' );
        case 'hiking' :
            wp_enqueue_style( 'locations', $templateuri.'/css/locations.css', '', false, 'all' );
        case 'nightlife' :
            wp_enqueue_style( 'locations', $templateuri.'/css/locations.css', '', false, 'all' );
        case 'page' :
            wp_enqueue_style( 'page', $templateuri.'/css/page.css', '', false, 'all' );
        case 'product' :
            wp_enqueue_style( 'product', $templateuri.'/css/product.css', '', false, 'all' );
        case 'reply' :
            wp_enqueue_style( 'forum', $templateuri.'/css/forum.css', '', false, 'all' );
        case 'topic' :
            wp_enqueue_style( 'forum', $templateuri.'/css/forum.css', '', false, 'all' );
        break;
        default : '';
    endswitch;

this one sometimes work sometimes not... On bbpress forums works fine, but on pages for example, it enqueues ALL the stylesheets...

Answer 1

The issue in your first block of code is syntax:

if( get_post_type() == ( 'activity' OR 'dining' OR 'heritage' OR 'hiking' OR 'nightlife' ) ) :

this isn't proper use of OR and will evaluate true regardless of what get_post_type() returns.

The issue in your second block is again syntax, you have to break; at the end of every switch case or the other statements after it get executed.