您可以使用专用函数**wcs_get_subscriptions_for_order()**检索$订阅ID。
这可能是你的密码

add_action('woocommerce_order_status_changed', 'action_order_status_changed');
function action_order_status_changed( $order_id ){
    $subscriptions_ids = wcs_get_subscriptions_for_order( $order_id, array( 'order_type' => 'any' ) );
    // We get all related subscriptions for this order
    foreach( $subscriptions_ids as $subscription_id => $subscription_obj )
        if($subscription_obj->order->id == $order_id) break; // Stop the loop

    // The subscription ID: $subscription_id 
    // The An instance of the Subscription object: $subscription_obj 
    // ...
}