我想限制它只添加一个类别的产品，不允许其他人使用 woocommerce

Question

I'm trying to limit it, so I can only add products with the same category and not allow others, returning a message, but when I try to add another product from the same category, it returns the defined error message. My code:

    // define your product category (can be term IDs, slugs or names)
    $category = 'courses';

    // close if cart is empty
    if( WC()->cart->is_empty() )
        return $passed;

    // check cart: search by course category items
    foreach ( WC()->cart->get_cart() as $cart_item ){
        if( has_term( $category, 'product_cat', $cart_item['product_id'] ) ) {
            // display a warning message
            wc_add_notice( __('Not possible to add courses together with products.', 'woocommerce' ), 'error' );
            // avoid adding to cart
            return false;
        }
    }
    return $passed;
}

Answer 1

I believe you only need to fix this line by adding "!" as you're looking to deny different categories:

if ( ! has_term( $category, 'product_cat', $cart_item['product_id'] ) )