Add a Woocommerce fee based on shipping class and item quantity - wordpress

Question

In Woocommerce I am trying to add a shipping fee if a cart item has a specific shipping class assigned to the related product. I would like this shipping fee to be multiplied by the cart item quantity…
I have this working when a product is added to the cart and the quantity is increased and the additional shipping fee is increased also. However if I add another product with the same shipping class and increase the quantity the additional fee does not increase.
This is my code:
// Add additional fees based on shipping class
function woocommerce_fee_based_on_shipping_class( $cart_object ) {
global $woocommerce;
// Setup an array of shipping classes which correspond to those created in Woocommerce
$shippingclass_dry_ice_array = array( 'dry-ice-shipping' );
$dry_ice_shipping_fee = 70;
// then we loop through the cart, checking the shipping classes
foreach ( $cart_object->cart_contents as $key => $value ) {
$shipping_class = get_the_terms( $value['product_id'], 'product_shipping_class' );
$quantity = $value['quantity'];
if ( isset( $shipping_class[0]->slug ) && in_array( $shipping_class[0]->slug, $shippingclass_dry_ice_array ) ) {
$woocommerce->cart->add_fee( __('Dry Ice Shipping Fee', 'woocommerce'), $quantity * $dry_ice_shipping_fee ); // each of these adds the appropriate fee
}
}
}
add_action( 'woocommerce_cart_calculate_fees', 'woocommerce_fee_based_on_shipping_class' ); // make it all happen when Woocommerce tallies up the fees
How can I make it work for additional cart items too?

Answer 1

Your code is a bit outdated and there is some mistakes. To add a fee based on product shipping class and cart item quantity use the following:
// Add a fee based on shipping class and cart item quantity
add_action( 'woocommerce_cart_calculate_fees', 'shipping_class_and_item_quantity_fee', 10, 1 );
function shipping_class_and_item_quantity_fee( $cart ) {
## -------------- YOUR SETTINGS BELOW ------------ ##
$shipping_class = 'dry-ice-shipping'; // Targeted Shipping class slug
$base_fee_rate = 70; // Base rate for the fee
## ----------------------------------------------- ##
$total_quantity = 0; // Initializing
// Loop through cart items
foreach( $cart->get_cart() as $cart_item ) {
// Get the instance of the WC_Product Object
$product = $cart_item['data'];
// Check for product shipping class
if( $product->get_shipping_class() == $shipping_class ) {
$total_quantity += $cart_item['quantity']; // Add item quantity
}
}
if ( $total_quantity > 0 ) {
$fee_text = __('Dry Ice Shipping Fee', 'woocommerce');
$fee_amount = $base_fee_rate * $total_quantity; // Calculate fee amount
// Add the fee
$cart->add_fee( $fee_text, $fee_amount );
}
}
Code goes in function.php file of your active child theme (or active theme). Tested and works.

Answer 2

If there is one shipping class in cart there should be no fees, but if there is more than one shipping class, then should be additional 1 Eur handling fee and increase for every another shipping class.
Situation 1: Product with shipping class (Warehouse 1) added to cart = No extra fees
Situation 2: Product with shipping class (Warehouse 1) added to cart, Product with another shipping class (Warehouse 2) added to cart = 1x Handling fee added to cart
Subtotals:
Products 2x - 10 Eur
Shipping - Free
Handling fee 1x - 1Eur
Total - 11 Eur
Situation 3: Product with shipping class (Warehouse 1) added to cart, Product with shipping class (Warehouse 2) added to cart, Product with shipping class (Warehouse 3) added to cart = 2x Handling fee added to cart
Subtotals:
Products 3x - 15 Eur
Shipping - Free
Handling fee 2x - 1Eur
Total - 12 Eur