navigation to diff views depends on If conditions

HI experts..

depends on the if condition i want to transfer the control to respective pages ..

for eg: if uname and pwd matches to admin the control have to move admin view.. or if it matches to emp then move emp view or else error view

and my doubt here is where we need write ie whether it is wdInit() or wdModify()

and how to write..

please explain in clear manner