I find that when I continue to say no to a certain food that I always end up over eating that food eventually.
So what I do is say yes but I keep it in check. If I am craving chocolate I have a mini candy bar. If I want ice cream I have a 1/2 cut and I measure it.
So when you are truely carving something have a small bit of it and in the long run it will help you from binging on it later on.