Is there a dress code in the casino?

This question is specific to: The Greenbrier
Dress Code:

Before 7:00pm in the Casino Club: Resort attire (collared sport shirts, sweaters, slacks and walking shorts). If denim is your attire preference, well-kept denim in a dark shade is ours.
 
After 7:00pm in the Casino Club: Jackets are required for gentlemen. If denim is your attire preference, well-kept denim in a dark shade is ours. Men’s hats and baseball caps are not permitted