Php 授权.NET CVV验证

我正在使用Authorize.NET PHP SDK。我添加了以下代码来验证CVV代码

$auth = new AuthorizeNetAIM;
$auth->amount = $amount;
$auth->card_num = $cc;
$auth->exp_date = $expiry_date;
$auth->x_card_code = $cc;

但现在我得到了以下例外：

Error: Uncaught exception 'AuthorizeNetException' with message 'Error: no field x_card_code exists in the AIM API.

---

如何验证CVV？

我使用了错误的字段名，它是card\U代码而不是x\U card\U代码

$auth = new AuthorizeNetAIM;
$auth->amount = $amount;
$auth->card_num = $cc;
$auth->exp_date = $expiry_date;
$auth->card_code = $cc;