storing data in gridview and gridview in cache

I want to design a website for e-shopping.I used class and generic list for shoppingcart.I want to store the selected item in a gridview and store  that gridview on a cache.but I dont  know how store  the selected item in a gridview and store that gridview in cache.I want to use session for users login and I don't want to use login control.I know that i must have a name for any cach(for any user),but I dont know how can I use that session for name of cach.what code should H write?please help me .thanks

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