Tell what you will do, i mean say thank you or say sorry or just shy away or ask Reason why. or run away or call someone to justify or ask for money or call police or react in a angry way. or smile at her, or just move as if nothing happened, or ask her phone no, or ask for a date, or give her a friendly kiss, or say what you did was right, or cry mummy

I might possibly slap the person back, but who knows? I might be so shocked that I might just stand there in disbelieve , wondering if I dreamt the whole thing

Why do you ask such a question?.. do you get slapped around in public a lot?

If you're on a leash it means you have displeased her.

If a woman slapped you until I knew why I would stay out of it.. Cause most likely you said something you should not have or put your hand where it did not belong. Specially due to what you said it seems you would not have known her if you were considering asking her out..

Never Happen when you know Kungfu.

That's quite an assumption based off a hypothetical question. Do you always assume the man was in the wrong?

I can honestly say ive never bern slapped by a woman, except my mom for having a smart mouth when i was a teenager.
Of course i didn't hit her back.
For one thing she's my mom. For another, i definitely had it coming.
That being said and your situation being different,
Why are you asking the question?
Did you get smacked?
If so, what briught that about?
Boys get slapped or punched for things like lewd comments, unwanted advances or putting hands where they don't belong. (To name a few reasons)

Furthermore, what are you going to do with the information/opinions you get in the responses?
If someone tells you they would hit her back, are you going to uses that to justify hitting a woman?