登入也设置cookie
setcookie('user_id', authlogin("user_id", "ENCODE"), time()+(3600*24*30), "/", ".lfb365.com");
authlogin()方法为将user_id进行编码,非内置方法
退出页清除cookie
setcookie("user_id", "", time()-3600, "/", ".lfb365.com");