We cruise every year and on a few different lines, I would ck on CruiseCritic.com and look around there and you will get all the answers to anything you might have a question about.
These days alot of the dress code rules have changed especially in the last 2 years. It isnt like it was and is now very relaxed. We have never done those elegant nights when we are on a cruise after all with having to pay for baggage now it adds up when you take all that with you.
Men were allowed nice dressier shorts and a polo type shirt and women a nice pr of capri's , sundress ETC and it was fine. Other than the dining room you can wear ANYTHING you want...anytime.