How to kill a session after logging out using php

Question

I have seen the following question and tried to adapt part of the answer but to no luck: \'How can i disable the back browser button after user press logout and destroy session?

Answer 1

login page:

checkUser($Username,$Password,$User_Type);
         if ($rowsCount!=0)
         {
              $_SESSION['user'] = $Username;
              header("Location:LoginViewController.php");

         } else {
              echo 'Bad user';
         }
    } else {
         echo 'Please, fill all inputs';
    }
} else {
    echo 'Bad form sent';
}
?>
 

// inputs
 

LoginViewController.php :

And add the headers to force the browser to revalidate the pages :

logout.php :