Prevent LinkButton post back OnClientClick not working. Why?

Question

I know there are plenty of answers surrounding this topic but I just cannot get this to work.

I need to prevent a link button posting back and the following code is

Answer 1

Right, figured it out. I needed to include the return statement in the OnClientClick attribute:

OnClientClick="return showConfirm(event);"

NOT

OnClientClick="showConfirm(event);"