Sample code for my 2D Zelda Unity tutorial which can be found here: http://www.teomaragakis.com/game-development/creating-2d-zelda-clone-unity/

playerController.cpp

using UnityEngine;
using System.Collections;

public class playerController : MonoBehaviour {
  private Animator animator;
  // Use this for initialization
  void Start () { animator = this.GetComponent(); }
  // Update is called once per frame
  void Update () {
    float v = Input.GetAxis("Vertical");
    float h = Input.GetAxis("Horizontal");
    ManageMovement(h, v);
  }
  void ManageMovement(float horizontal,float vertical) {
      
    if (horizontal != 0f || vertical != 0f) {
      animator.SetBool ("moving", true); animateWalk (horizontal, vertical);
    } else {
      animator.SetBool ("moving", false);
    }
      
    Vector3 movement = new Vector3 (horizontal,vertical, 0);
    rigidbody2D.velocity = movement;
  }
  void animateWalk(float h,float v) {
    if(animator){
      if ((v > 0)&&(v>h)) {
        animator.SetInteger ("Direction", 1);
      }
      if ((h > 0)&&(v<h)) {
        animator.SetInteger ("Direction", 2);
      }
      if ((v < 0)&&(v<h)) {
        animator.SetInteger ("Direction", 3);
      }
      if ((h < 0 )&&(v>h)) {
        animator.SetInteger ("Direction", 4);
      }
    }
  }
}