UGUI检测鼠标进入退出

引用：
using UnityEngine.EventSystems;
继承：
public class Method : EventTrigger
重写：
(1)进入：
public override void OnPointerEnter(PointerEventData eventData)
(2)退出：
public override void OnPointerExit(PointerEventData eventData)
在EventTrigger中还有很多其他函数，如拖拽，移动，点击，取消等等
例：

using UnityEngine;
using UnityEngine.UI;
using UnityEngine.EventSystems;

public class BackGroundShow : EventTrigger
{
    public override void OnPointerExit(PointerEventData eventData)
    {
        Debug.Log("Exit");
        //退出动画
        Animation ani = this.transform.parent.gameObject.GetComponent<Animation>();
        ani["UIAnimation"].speed = 1;
        ani.Blend("UIAnimation");
    }

    public override void OnPointerEnter(PointerEventData eventData)
    {
        Debug.Log("Enter");
        //进入动画
        Animation ani = this.transform.parent.gameObject.GetComponent<Animation>();
        ani["UIAnimation"].speed = -1;
        ani.Blend("UIAnimation");
    }
}