Directional animation?

Hello, I am very new here. I wondering if it was possible to have 1 animation recognize directional parameters and play the correct animation. Or would i have to create several animation and directional variables that will tell unity which animation to play. In short what is the most efficient way to do 8 directional animation (aka topdown player animation)
Thank you for your time.

http://forum.unity3d.com/threads/212172-Animator-state-machine-for-top-down-2d-games-with-non-rotational-sprite-animation