LinkButton Click Event

I have this problem ..
I have one “Login” linkbutton and one “UserList” linkbutton on one masterpage. When the user is logged in, and he clicks “UserList” linkbutton, the UserList Page which has the masterpage mentioned above, opens.(This i have achieved).

but if the user is not logged in and he clicks “UserList”, the “Login” linkbutton’s click should be called. how can i achieve this? Please Help..

LinkButton Click Event