Forms Authentication

I am using 'forms' authentication mode in my web application. I am not using the formsAuthenticate method to verify credentials, but instead I am using a function I have written that checks if the user is found in the database or not, and based on that I redirect the user to the home page.

 I would like to deny users and allow roles in the webconfig from accessing certain webpages in my webapplication. How can my code behind see the roles defined in the webconfig file? Are they defined somewhere in the database?

 

Any advise is appreciated.
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