Is this dress okay for a posh dinner dance?

[pipicalzaslargas]

I have been invited at short notice at a posh dinner dance at a private school next Friday. Dress code is black tie. Do you think this dress is okay? www.whistles.com/women/sale/dresses/olivia-lace-dress-24251.html?dwvar_olivia-lace-dress-24251_color=Multicolour#start=1

I am short so it fits just below my knees. It does look very nice on me, I just don't know if it's appropriate as I haven't been to one of these functions for years!

Men can just buy a black suit and bow tie

No they can't.

There needs to be a sticky link to Debretts on here; some of the dress code advice that gets trotted out is just terrible.

OP, black tie is pretty vague these days. It depends on so much; the event, your age, who else will be there, the venue - loads of variables.
Ask other mothers or housemistress about the usual expectations/traditions for that particular event. I'm also 5'2 and I would wear that dress for a black tie event if it was a less traditional setting.
None of the shoes are suitable though. Nothing that shows your toes, and nothing with a high strap as us shorties can't get away with it, makes you look stumpy.

What do you think black tie is?

Black tie is a dinner suit for men (as opposed to a lounge suit) with a dress shirt and bow tie. In my view anyway, don't know what debretts would say!

It's not a black suit with a bow tie. It's dress trousers, a dinner jacket, dress shirt and bow tie.

Thank god you came around from your fainting fit