WooCommerce - 在Ajax更新后计算购物车总数

I have a small bit of code which calculates the cart total (excluding taxes) and outputs a Free Shipping upsell, if the cart total is less than $50.

// Shipping Upsell
/**
 * Checks the cart for the Total excluding taxes
 * @param $total_required
 * @return bool
 */
function qualifies_basedon_cart_total( $total_required ) {
    /*
     * We only want to run this on the cart or checkout page
     * If the cart subtotal is less than $total_required for free shipping, return true
     */
if( is_cart() || is_checkout () ) {
    if( WC()->cart->subtotal_ex_tax < $total_required ) {
        return true;
    }
}
// do nothing
return false;
}

function shipup(){
    // tests if total is below $50 and displays upsell if query returns ture
    if( qualifies_basedon_cart_total( 50 ) ) {
    echo "<div class =\"shipup\"><h3>Free Shipping</h3>
<p>Get free shipping on all orders over $50!</p></div>";
    }
}

add_action ('woocommerce_cart_collaterals','shipup', 1);

The code above works great on the initial page load, but after changing the quantity on the cart page and selecting 'Update Cart' the code I have above (in functions.php) does not adjust itself based on the new cart total. enter image description here

I believe the update cart button uses AJAX and my code is not able to tap into that. How can AJAXIFY my code so that it works based on the dynamic cart total?

If you're using WooCommerce 2.6 and above, WC has created a way to do this without additional code on your end.

You'll need to setup "Shipping Zones" under "WooCommerce" -> "Settings" -> "Shipping" -> "Shipping Zones".

For example, I have "Local" and "United States" shipping zones.

  1. For the "United States" shipping zone, then I created a "Shipping Method" (click on the zone to add a shipping method, then click the grey button titled "Add shipping method").
  2. Select the "Free Shipping" method and click "Add shipping method".
  3. Then click "Settings" under the "Free Shipping" method.
  4. At this point, you have the option to set when the free shipping method applies. Use the dropdown for "Free Shipping Requires..." and select "A minimum order amount" and type "50" in the "Minimum Order Amount" field.
  5. Then click "Save Changes".

Now when the cart's total is $50 or more, then free shipping will be available.

<?php

/* Update cart total on quantity change */

function cart_select_change_js() {
?>
    <script type="text/javascript">
        jQuery(document).ready(function($){
            $(".product-quantity .quantity_select select.qty").change(function(){
                $("section.entry .woocommerce").append('<div style="display:none" class="blockUI"></div>');
                $("section.entry .woocommerce").append('<div style="z-index: 1000; border: medium none; margin: 0px; padding: 0px; width: 100%; height: 100%; top: 0px; left: 0px; background: url(&quot;/wp-content/plugins/woocommerce/assets/images/ajax-loader@2x.gif&quot;) no-repeat scroll center center / 16px 16px rgb(255, 255, 255); opacity: 0.6; cursor: wait; position: absolute;" class="blockUI blockOverlay"></div>');
                $(".actions input.button").click();
            });
        });
    </script>
<?php
}
add_action('woocommerce_after_cart', 'cart_select_change_js', 10);
?>

Try this code snippet