hmmm....those "codes" can mean totally different things depending on where you are and what type of function
im sure business casual in some big city is slacks and button up w/ no tie, maybe even sleeves rolled up
business casual here is nice jeans, boots/loafers, and a polo
Never been to a "black tie" event, dont really wanna speak on what I dont know but I would take that as business suits, but your best.....tailor made shit