在wpf中，当我的系统关闭或互联网连接消失时，我需要使用wcf服务将标志更新为false到数据库

In my wpf application when user login i will update Islogin=true when user is logout im updating Islogin=false when my system is crashed or shut down or internet connection gone then this case how to handle,im using wcf service for thisIn my wpf application when user login i will up