how to shift from one tab to other programmetically?

[abcdef]

when we are trying to shift one tab to other one event should occur, can any one tell what is the event,how and where we have to write the event??? give example.
if he successfully login in first tab only then second tab will open,if he doesnt login in first and tries to open the second tab message should appear...
can any one help me??

[RhysW]

have you tried this yourself? do you have any code trying to do this at all yet? If not how do you think you might go about it?

Learning the answer is good, but learning how to get the answer is better. If you haven't tried this yourself yet then its less likely you will get help here, sites like these tend to guide not give. Show us an attempt and ill be happy to help guide you to improving it to do what you want it to do!

RhysW