makeup setting spray vs primer?

answers1: No primer will keep your makeup on all day no matter how
much it promises to. Primers are for filling in lines/pores and
creating a smooth canvas for makeup application. <br>
<br>
Sprays however keep makeup in place all day and control oil/sweat to
an extent. <br>
<br>
The best sprays are from Skindinavia, Motives, Premiere Producrts inc,
Ben Nye, Kryolan and OCC Cosmetics. <br>
<br>
Urban Decay, Mac, Mufe, ELF, Model in a Bottle, Kat Von D and others
that I've tried don't really work. <br>
<br>
Anyway if you need to fill in line/pores but you also have trouble
keeping your makeup on because of oily skin or heat outside or you
just have makeup with not very good staying power you need both.
answers2: Not necessarily, but some people do, some people don't. It's
up to you. If you find your makeup still wears off the day without the
primer, then use a primer.
answers3: Only if your foundation is not staying on all day
answers4: not really but its best to