How check role user?
I use silverligth bisnes aplication
<StackPanel x:Name="StackPanelControlsAdmin" >
see admin
</StackPanel>
<StackPanel x:Name="StackPanelControlsUser" >
see user
</StackPanel>
<StackPanel x:Name="StackPanelControlsAdminUser" >
see admin and user
</StackPanel>
there might be some webcontext.current.user
http://msdn.microsoft.com/en-us/library/ee942449(v=vs.91).aspx