Add a dynamic fee based on a select field in WooCommerce Checkout

I am using Update fee dynamically based on radio buttons in Woocommerce checkout answer code solution that worked very well for me to add checkbox fields with a different price for each one, and the price changes are reflected in the checkout.

But I need some help: When I select a type of packaging with additional tax, it appears in the backend in the order area, but only shows the price, and I would like to show the title as well.

The checkbox options have:

'options' => array (
    'bag' => __ ('In a bag' .wc_price (3.00), $ domain),
    'box' => __ ('In a gift box' .wc_price (9.00), $ domain),
),

How to make it show the name on the order? Also if it’s possible to change the checkboxes to select field instead?

Answer

I have made some changes to the original code that will:

• Display a custom select field (instead of radio buttons input fields)
• Display a custom error notice if customer has not selected a packing option
• Display the selected packing type everywhere (on orders and email notifications)

The code:

// Add a custom select fields for packing option fee
add_action( 'woocommerce_review_order_after_shipping', 'checkout_shipping_form_packing_addition', 20 );
function checkout_shipping_form_packing_addition( ) {
    $domain = 'woocommerce';

    echo '<tr class="packing-select"><th>' . __('Packing options', $domain) . '</th><td>';

    $chosen   = WC()->session->get('chosen_packing');

    // Add a custom checkbox field
    woocommerce_form_field( 'chosen_packing', array(
        'type'      => 'select',
        'class'     => array( 'form-row-wide packing' ),
        'options'   => array(
            ''    => __("Choose a packing option ...", $domain),
            'bag' => sprintf( __("In a bag (%s)", $domain), strip_tags( wc_price(3.00) ) ),
            'box' => sprintf( __("In a gift box (%s)", $domain), strip_tags( wc_price(9.00) ) ),
        ),
        'required'  => true,
    ), $chosen );

    echo '</td></tr>';
}

// jQuery - Ajax script
add_action( 'wp_footer', 'checkout_shipping_packing_script' );
function checkout_shipping_packing_script() {
    // Only checkout page
    if ( is_checkout() && ! is_wc_endpoint_url() ) :

    WC()->session->__unset('chosen_packing');
    ?>
    <script type="text/javascript">
    jQuery( function($){
        $('form.checkout').on('change', 'select#chosen_packing', function(){
            var p = $(this).val();
            console.log(p);
            $.ajax({
                type: 'POST',
                url: wc_checkout_params.ajax_url,
                data: {
                    'action': 'woo_get_ajax_data',
                    'packing': p,
                },
                success: function (result) {
                    $('body').trigger('update_checkout');
                    console.log('response: '+result); // just for testing | TO BE REMOVED
                },
                error: function(error){
                    console.log(error); // just for testing | TO BE REMOVED
                }
            });
        });
    });
    </script>
    <?php
    endif;
}

// Php Ajax (Receiving request and saving to WC session)
add_action( 'wp_ajax_woo_get_ajax_data', 'woo_get_ajax_data' );
add_action( 'wp_ajax_nopriv_woo_get_ajax_data', 'woo_get_ajax_data' );
function woo_get_ajax_data() {
    if ( isset($_POST['packing']) ){
        $packing = sanitize_key( $_POST['packing'] );
        WC()->session->set('chosen_packing', $packing );
        echo json_encode( $packing );
    }
    die(); // Alway at the end (to avoid server error 500)
}

// Add a custom dynamic packaging fee
add_action( 'woocommerce_cart_calculate_fees', 'add_packaging_fee', 20, 1 );
function add_packaging_fee( $cart ) {
    if ( is_admin() && ! defined( 'DOING_AJAX' ) )
        return;

    $domain      = "woocommerce";
    $packing_fee = WC()->session->get( 'chosen_packing' ); // Dynamic packing fee

    if ( $packing_fee === 'bag' ) {
        $label = __("Bag packing fee", $domain);
        $cost  = 3.00;
    } elseif ( $packing_fee === 'box' ) {
        $label = __("Gift box packing fee", $domain);
        $cost  = 9.00;
    }

    if ( isset($cost) )
        $cart->add_fee( $label, $cost );
}

// Field validation, as this packing field is required
add_action('woocommerce_checkout_process', 'packing_field_checkout_process');
function packing_field_checkout_process() {
    // Check if set, if its not set add an error.
    if ( isset($_POST['chosen_packing']) && empty($_POST['chosen_packing']) )
        wc_add_notice( __( "Please choose a packing option...", "woocommerce" ), 'error' );
}

Code goes in functions.php file of your active child theme (or active theme). Tested and works.

The error message when customer hasn’t chosen a packing option: