当客户使用WooCommerce进行购买时，如何将客户账单信息添加到MailChimp Group

我已经上下寻找解决这个问题，但没有运气。 我想我错过了一些非常基本的东西，因为修复听起来很简单。

我正在尝试将客户帐单详细信息添加到MailChimp Group。

它适用于销售在线课程的网站。

我想发生的是：用户在网站上进行购买，并根据他们的购买自动注册相应的MailChimp Group（即用户购买每月视频课程，被添加到"每月视频课程"MailChimp Group。

我已经编写了一些代码，但它不起作用（我收到"未定义的变量"错误）。我不确定变量/语法是否正确。 我绝不是编码员。

有人可以帮助我吗？

这是我的代码（我放在函数中.php）：

function pass_wp_to_mc() {
require_once 'inc/MCAPI.class.php';
require_once 'inc/config.inc.php'; //contains apikey
require_once 'wp-content/plugins/woocommerce/classes/class-wc-checkout.php';

$api = new MCAPI($apikey);
// Grabs the WooCommerce Product IDs and associates them with the Mailchimp Group IDs - users are put into Groups based on product purchase.
if ($product_id == 42) {
$mailchimpGroupingId = 1;
$mailchimpGroup = 'Monthly';
} elseif ($product_id == 142) {
$mailchimpGroupingId = 1;
$mailchimpGroup = 'Weekly';
} else ($product_id == 144); 
$mailchimpGroupingId = 1;
$mailchimpGroup = 'Audio';
}
$merge_vars = array(
'FNAME' => $billing_first_name,
'LNAME'=> $billing_last_name,
'EMAIL'=> $billing_email,
'GROUPINGS'=>array(
array('id'=>$mailchimpGroupingId, 'groups'=>$mailchimpGroup),
)
);
$listId = 33833; //List ID found inside MailChimp on the page for your List
$my_email = '$email'; 
$double_optin = false; // People are automatically added in to List
$update_existing = true; // Will update users if they are already on the list

$retval = $api->listSubscribe( $listId, $my_email, $merge_vars, $double_optin, $update_existing);
if ($api->errorCode){
echo "Unable to load listSubscribe()!'n";
echo "'tCode=".$api->errorCode."'n";
echo "'tMsg=".$api->errorMessage."'n";
} else {
echo "Subscribed - look for the confirmation email!'n";
}

我的问题是：这段代码是否正确？如果是这样，函数.php是放置它的地方吗？如果是这样，我如何"调用"它以及我将在哪里调用 - WordPress 文件？ 呜？谢谢.php？结账.php？购物车.php？

非常感谢任何帮助 - 我已经尝试解决这个问题数周了！

更新：我想通了！ 首先，代码不正确。 这是有效的：

require_once dirname(__FILE__).'/inc/MCAPI.class.php';
require_once dirname(__FILE__).'/inc/config.inc.php';
add_action('woocommerce_checkout_order_processed', 'get_info');
function get_info($order_id) { 
global $woocommerce;
$order = new WC_Order( $order_id );
$firstname = $order->billing_first_name;
$lastname = $order->billing_last_name;
$email = $order->billing_email;
$product_id=unserialize($order->order_custom_fields["_order_items"][0]);
$product_id=$product_id[0]['id'];
    global $apikey;
$api = new MCAPI($apikey);
if ($product_id == *GET THIS ID AT THE EDITING SCREEN OF YOUR PARTICULAR WOOCOMMERCE PRODUCT*) {
$mailchimpGroup = '*ENTER THE NAME OF YOUR MAILCHIMP GROUP (NOT THE TITLE)*';
} elseif ($product_id == *GET THIS ID AT THE EDITING SCREEN OF YOUR PARTICULAR WOOCOMMERCE PRODUCT*) {
$mailchimpGroup = '*ENTER THE NAME OF YOUR MAILCHIMP GROUP (NOT THE TITLE)*';
} else ($product_id == *GET THIS ID AT THE EDITING SCREEN OF YOUR PARTICULAR WOOCOMMERCE PRODUCT*); 
$mailchimpGroup = '*ENTER THE *NAME* OF YOUR MAILCHIMP GROUP (NOT THE TITLE)*';
$merge_vars = array(
                    'FNAME' => $firstname,
                    'LNAME'=> $lastname,
                    //'EMAIL'=> $email,
                    'GROUPINGS'=>array(
                        array('name'=>'*ENTER THE TITLE OF YOUR MAICHIMP GROUP (NOT THE NAME)', 'groups'=>$mailchimpGroup),
                        )
                    );
$listId = 'YOUR LIST ID HERE'; //List ID found inside MailChimp on the page for your List
$my_email = $email; 
$double_optin = false; // People are automatically added in to List
$update_existing = true;    // Will update users if they are already on the list               

$retval = $api->listSubscribe( $listId, $my_email, $merge_vars, $double_optin, $update_existing);