i have a login form , which calls the main form of my application ( a form for navigating to other forms in my app ) ,
when the user logs on i assign the user_id to a global variable , to use it for controlling the user's privileges on the forms . i.e ( open form1 , form2 , not form 3 , etc .. ) .
i know i should erase global variables , but i do not know when ,
i want to erase all global variables if there is no open forms at all , can i do so ?