I haven't myself but I've dealt with that for others. If you turn the keyboard upside down right when it happens and use compressed air to blow it out, it will generally be OK. If it dries up, there isn't much you can do except replace the keyboard. If it's a laptop then you'll have to have a Tech check it out to see if it can be fixed. So much sugar in those things that it will dry and gum everything up!
I spilled a whole cup of coffee on the keyboard, it survived the spill damage but it's not been the same and not much you can do. All I did was let it dry out and wipe off the keyboard.