Using roles in asp.net and showing /hiding data depending on assigned role?

hi,
I am using LoginView  and within the logged in template I call a method in
Code behind which checks database by UserId.  Depending on condition I show a Client or a Customer li links
in dropdown list.

My question is how can I replaced the below using ROLES instead as I have Client and Customer roles in database.
will this also be more effficient?

                  <li>                   <asp:LoginView runat="server" ID="LoginView1">          <AnonymousTemplate>                              &nbs ...