设置反映在 Woocommerce 3 中的订单上的折扣购物车商品价格

Question

我在我的 functions.php 中使用此代码对我的产品应用 10% 的折扣，从购物车中的第二个开始：

function add_discount_price_percent( $cart_object ) {

    global $woocommerce;

    $pdtcnt=0;

    foreach ($woocommerce->cart->get_cart() as $cart_item_key => $cart_item) {
        $pdtcnt++;

        $oldprice = 0;
        $newprice = 0;


        if($pdtcnt>1) { // from second product

            $oldprice = $cart_item['data']->price; //original product price      

            // echo "$oldprice<br />";

            $newprice = $oldprice*0.9; //discounted price
            $cart_item['data']->set_sale_price($newprice);
            $cart_item['data']->set_price($newprice);
            $cart_item['data']->set_regular_price($oldprice);

        }     
    }

    WC()->cart->calculate_totals();

}


add_action( 'woocommerce_before_cart', 'add_discount_price_percent', 1);

add_action( 'woocommerce_before_checkout_form', 'add_discount_price_percent', 99 );

价格在购物车和结帐页面中都正确显示，但是当我使用 PayPal 沙盒测试我的付款时，我看到并且必须支付全价，因为折扣被忽略了。

如果我在提交按钮之前回显折扣价格，我会得到正确的价格：

function echo_discount_before_checkout_submit() {

    if ( is_admin() && ! defined( 'DOING_AJAX' ) )
        return;

    foreach ( WC()->cart->get_cart() as $key => $value ) {
        echo $value['data']->price . "<br />";
    }

}
add_action( 'woocommerce_review_order_before_submit', 'echo_discount_before_checkout_submit', 99 );

如何向 PayPal 发送正确的折扣价格？

编辑：@LoisTheAtzec 的回复非常好，但如果数量超过 2，即使是第一个产品，我也需要 10% 的折扣：我正在尝试此代码，但我无法获得正确的值。

// If it is the first product and quantity is over 1
if ($count === 1 && $cart_item['quantity'] >= 2) {

        // get unit price
        $unit_price = $cart_item['data']->get_price();

        // get quantity to discount (total - 1)
        $discounted_quantity = $cart_item['quantity'] - 1;

        // get total discount amount (on total quantity - 1) 
        $discounted_amount = ($unit_price * $discounted_quantity) * 0.9;

        // add first non discounted price to total discount amount
        $total_discounted_price = $unit_price + $discounted_amount;

        // distribute discount over total quantity and get new unit price 
        $distributed_unit_discount = $total_discounted_price / $cart_item['quantity'];

        // set new unit price
        $cart_item['data']->set_price($distributed_unit_discount);
    }

2018 年 9 月 6 日更新

我在登录用户时遇到了一个奇怪的行为，可能取决于插件之间的一些冲突或我使用的主题 (Avada)：折扣应用了两次，所以我不得不阻止此代码添加到我的函数中：

// Set the discounted price on 2nd item and
add_action('woocommerce_before_calculate_totals', 'add_discount_percentage_on_2nd_item', 999, 1);  

function add_discount_percentage_on_2nd_item($cart) {
    if (is_admin() && !defined('DOING_AJAX'))
        return;

if ( did_action( 'woocommerce_before_calculate_totals' ) >= 2 )
    return; 

希望对你有帮助。

Answer 1

在购物车对象中，唯一可以真正改变并产生影响的是有效价格。
更改购物车商品中的常规价格或促销价格无效。

尝试以下操作，这将改变第二个购物车及以后的价格，并且数据将正确传递到 Paypal：

// Calculate and save as custom cart item data the discounted price
add_filter('woocommerce_add_cart_item_data', 'add_custom_cart_item_data', 20, 3);

function add_custom_cart_item_data($cart_item_data, $product_id, $variation_id) {
    // HERE set the percentage rate to be applied to get the new price
    $percentage = 10; // 10%

    $_product_id = $variation_id > 0 ? $variation_id : $product_id;

    $product = wc_get_product($_product_id); // The WC_Product Object
    $base_price = (float) $product->get_price(); // Get the product active price

    // Save the calculated discounted price as custom cart item data
    $cart_item_data['discounted_price'] = $base_price * ( 100 - $percentage ) / 100;

    return $cart_item_data;
}

// Set the discounted price on 2nd item and
add_action('woocommerce_before_calculate_totals', 'add_discount_percentage_on_2nd_item', 20, 1);
function add_discount_percentage_on_2nd_item($cart) {
    if ( is_admin() && ! defined( 'DOING_AJAX' ) )
        return;

    if ( did_action( 'woocommerce_before_calculate_totals' ) >= 2 )
        return;

    $count = 0;

    // Loop through cart items
    foreach($cart->get_cart() as $cart_item) {
        $count++; // Increasing

        // On 2nd cart item or more set the calculated discounted price
        if ($count >= 2 && isset($cart_item['discounted_price']))
            $cart_item['data']->set_price($cart_item['discounted_price']);
    }
}

代码进入活动子主题（或活动主题）的 function.php 文件中。经过测试并且可以工作。

---

附加 - 如果购物车内容数超过 2，则所有商品均可享受折扣。

您将使用与上面相同的第一个挂钩函数代码。
您将使用以下内容替换第二个挂钩函数：

// Set a discounted price on cart items when cart content count is over 2
add_action('woocommerce_before_calculate_totals', 'add_discount_percentage_on_2nd_item', 20, 1);
function add_discount_percentage_on_2nd_item($cart) {
    if ( is_admin() && ! defined( 'DOING_AJAX' ) )
        return;

    if ( did_action( 'woocommerce_before_calculate_totals' ) >= 2 )
        return;

    // Get the total items count
    $total_count = $cart->get_cart_contents_count();

    // if total count is below 2 we exit
    if( $total_count < 2 ) 
        return; // Exit

    // Loop through cart items
    foreach($cart->get_cart() as $cart_item) {

        // Set the calculated discounted price
        if (isset($cart_item['discounted_price']))
            $cart_item['data']->set_price($cart_item['discounted_price']);
    }
}

代码进入活动子主题（或活动主题）的 function.php 文件中。它应该可以工作。

---

加法2

• 只有第一个购物车商品是全价的，下一个数量的第一个商品打折）
• 所有蝾螈购物车商品都打折。

代码：

// Calculate and save as custom cart item data the discounted price
add_filter('woocommerce_add_cart_item_data', 'add_custom_cart_item_data', 20, 3);

function add_custom_cart_item_data($cart_item_data, $product_id, $variation_id) {
    // HERE set the percentage rate to be applied to get the new price
    $percentage = 10; // 10%

    $_product_id = $variation_id > 0 ? $variation_id : $product_id;

    $product = wc_get_product($_product_id); // The WC_Product Object
    $base_price = (float) $product->get_price(); // Get the product active price

    // Save the normal active product price as custom cart item data
    $cart_item_data['normal_price'] = $base_price;

    // Save the calculated discounted price as custom cart item data
    $cart_item_data['discounted_price'] = $base_price * ( 100 - $percentage ) / 100;

    return $cart_item_data;
}

// Set the discounted price on 2nd item and
add_action('woocommerce_before_calculate_totals', 'add_discount_percentage_on_2nd_item', 20, 1);

function add_discount_percentage_on_2nd_item($cart) {
    if (is_admin() && !defined('DOING_AJAX'))
        return;

    if ( did_action( 'woocommerce_before_calculate_totals' ) >= 2 )
        return; 

    // Initializing variables
    $count = 0;
    $first_item = true

    // Loop through cart items
    foreach($cart->get_cart() as $cart_item) {
        // 1. First cart item
        if ( isset($cart_item['discounted_price']) && isset($cart_item['normal_price']) && $first_item ){
            if( $cart_item['quantity'] > 1 ){
                $normal_price   = (float) $cart_item['normal_price'];
                $discount_price = (float) $cart_item['discounted_price'];
                $quantity       = (int) $cart_item['quantity'];

                // The first item is at full price and others at discounted price
                $cart_item['data']->set_price( $normal_price + ( $discount_price * ($quantity - 1) ) );
            }
            $first_item = false; // We switch it to false as it is the first cart item
        }
        // 2. All next items (at discounted price
        elseif ( isset($cart_item['discounted_price']) && ! $first_item ){
            // Set the discounted price
            $cart_item['data']->set_price($cart_item['discounted_price']);
        }
    }
}

代码进入活动子主题（或活动主题）的 function.php 文件中。它应该可以工作。

Answer 2

支付网关接受“regular_price”并且您已通过旧价格。
尝试用新的价格变量设置regular_price，也许它可以工作。

//update _regular_price
$wpdb->update( 
    $wpdb->postmeta, 
    array( 'meta_value' => $default_product_price ), 
    array( 'meta_key' => '_regular_price' )
);

或者按照上面的代码更新数据库中的价格。这肯定会对你有所帮助。