if ($user_id == NULL || $user_name == NULL || $user_logged == NULL) { $user_id = \'-1\'; $user_name = NULL; $user_logged = NULL; } if ($user_admin == NUL
1.
if(!($user_id || $user_name || $user_logged)){ //do your stuff }
2 . No. I actually did not understand why you write such a construct.
3 . Put all values into array, for example $ar["user_id"], etc.