They are both intense feelings you have towards someone..Affection I believe is the first step towards love,it's when you start to have feelings for someone such as feelings of admiration,concern,and respect.This I believe can lead to love which is a deeper more intense feeling.An overwhelming feeling,something you can't describe really because everyone's perception on what love is-is different.
When in love,the happiness and safety of the one you love is the most important thing in your life.Whereas with attraction and affection there is simply a desire and interest for another that may come or go as situations arise.
love is a feeling which stays longer. you care for that person. you even feel jealous when someone approaches him or her. it's something pure and holy. some call it a form of sacrifice. But attraction is short-lived. you just go after anyone and everyone.it is when only the outer beauty attracts you. But in case of love, you are attracted by the inner beauty of the person. you love that person and pour affection on him or her. still then, in the end you can say that both affection and attraction are the forms of love.
Affection, love and attraction are different things. Attraction is temporary where as love lasts. Affection can exist without existence of love or attraction. We can be affectionate to anyone but in 'love' with anyone... I hope you get it.. :)