订购已完成邮件时的Woocommerce切换语言

Question

我正在使用woocommerce + wpml，我想以编程方式设置完成的电子邮件订单。 我正在尝试使用$ sitepress-＆gt; switch_lang（），但似乎无效。

add_action( 'woocommerce_order_status_completed', 'mysite_woocommerce_order_status_completed' );

function mysite_woocommerce_order_status_completed($order_id)
{
    global $sitepress;
    $sitepress->switch_lang('en', true);
    if($sitepress->get_current_language() == 'en')
    {
       $mailer = WC()->mailer();
       $recipient = 'customer@mail.com';
       $subject = 'Your Order has been completed';
       $content = get_processing_notification_content_completed( $order, $subject, $mailer );
       $headers = "Content-Type: text/html\r\n";

       $mailer->send( $recipient, $subject, $content, $headers );
    }
}

function get_processing_notification_content_completed( $order, $heading = false, $mailer ) {
    $template = 'emails/customer-completed-order.php';

    return wc_get_template_html( $template, array(
      'order'         => $order,
      'email_heading' => $heading,
      'sent_to_admin' => true,
      'plain_text'    => false,
      'email'         => $mailer
    ) );
}

虽然我使用“switch_lang（）”，但邮件继续以意大利语显示。