In Norway carrying a knife...any type of sharp object in fact, in public is illegal.

What saves the day is that doing so for an "honorary purpose" i.e bushcraft, fishing or for professional use like a carpenter at work etc is allowed.
Also there was acase where a man was fined and the knife confiscated while he was peeling an apple right outside the Court House in Oslo. He rfused to accept the fine, and was taken to court where he won the case. Using a pen knife to peel an apple is allowed. So make sure to bring apples with your pen knife...