[2005] job cart/shopping cart

Hello all,
i'm doing a library management system using VS 2005 c#.net for my eduaonal purpose.
here i want to use cart like shopping cart/job cart.

here Student will select books, then they will save books in cart. Then system will ask for user ID & password. if they provide then save books in their cart, i already did this, problem is:if they dont have userID i redirect them in log-in page (where normally user can login also without selecting book). But when they create new user how do i can get their selected books and how i can track that this user selected books so that i need to save books according newly created users??
Please give me idea's..if possible code also.
Thanks

i'm assuming you have to have a class that holds these books, along with the userid you're using (sessionID perhaps?)
you can save this class Book to a List that's attached to the sessionID, and then when new user is created, and logs in, attach the List to this new user.

How are you currently maintaining your cart? It must either be in a cookie or in a session variable. In either case, once they login, you only need to re-read the values in the cookie or session variable.