$lost_ids = array_diff($all_ids,$old_ids); //array_diff,$old_ids不可以为null
否则返回为null;array_diff起不到效果~~~
$lost_ids = array_diff($all_ids,$old_ids); //array_diff,$old_ids不可以为null
否则返回为null;array_diff起不到效果~~~
转:https://www.cnblogs.com/pansidong/p/7464497.html