As Dave stated, no shorts are allowed for dinner in the main dining room(s). If you plan on wearing shorts you will have to go to the Windjammer for dinner. On casual nights, I usually wear khakis and a button down shirt, no tie or jacket.
On formal nights, I wear dress slacks, a shirt and tie, and jacket.
2007 - Majesty of the Seas (Bahamas)
2009 - Enchantment of the Seas (Western Caribbean)
2010 - Freedom of the Seas (Western Caribbean)
2013 - Golden Princess (Alaska, roundtrip from Seattle)