Wordpress woocommerce根据数量向购物车添加费用

我想根据数量增加费用。 例如：如果购物车中的数量=5，则要添加的费用应为4美元， 如果购物车中的数量=7，则要添加的费用应为8$

我试过这个代码来获取数量

add_action('woocommerce_before_calculate_totals', 'woocommerce_custom_surcharge');

function woocommerce_custom_surcharge() {
    global $woocommerce;
$amount =  $woocommerce->cart->get_cart_item_quantities();
if($amount==5)
{
    $excost = 7;
    }
    else if($amount==7){
    $excost = 8;
    }
    $woocommerce->cart->add_fee('Charges delivery', $excost, $taxable = false, $tax_class = '');
}

请帮我做同样的事情。

请试试这个

function woocommerce_custom_surcharge(){ 
global $woocommerce;
//Getting Cart Contents. 
$cart = $woocommerce->cart->get_cart();
//Calculating Quantity
foreach($cart as $cart_val => $cid){
        $qty += $cid['quantity']; 
    }
//Your Condition
if($qty==5)
{
    $excost = 7;
    }
    else if($qty==7){
    $excost = 8;
    }

    $woocommerce->cart->add_fee('Charges delivery', $excost, $taxable = false, $tax_class = '');


}

我发现我们需要通过汇总购物车的价值来获得购物车的数量。希望这能解决您的问题