Disabled the address bar of the explorer till the user is logged in

hi Experts , I have created an asp.net application where user logged in with different role such as super admin , admin etc

I just wanted to know is it possible to disabled the address bar of they explorer(internet ex,firefox etc)  till the time user is logged in and when  user logged out till will active again..

Or Is there any other way of doing it. I just want logged in user not to change the address bar till the time he/she is logged in..

I know about the encryption and decryption concepts but i dont want to use

problem :- seach page helps in searching employ on click of employeeid display the page for update

and the same page will be used for adding new employee without query sting 

eg empdetails.aspx?empid=121 will update the details

and empdetails.aspx will add new emp details

help me

experts

 
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