Unity通过代码修改按钮点击效果

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
using UnityEngine.EventSystems;

public class ButtonChangeColor : MonoBehaviour, IPointerEnterHandler, IPointerExitHandler, IPointerDownHandler,IPointerUpHandler
{
 private Text m_Text;
 private Image image;
 public Sprite[] sprites;

 void Awake()
 {
  m_Text = transform.Find("Text").GetComponent<Text>();
  image = GetComponent<Image>();
 }
 /// <summary>
 /// 鼠标移入事件
 /// </summary>
 /// <param name="eventData"></param>
 public void OnPointerEnter(PointerEventData eventData)
 {
  image.sprite = sprites[1];
  m_Text.color = Color.red;
 }

 /// <summary>
 /// 鼠标移出事件
 /// </summary>
 /// <param name="eventData"></param>
 public void OnPointerExit(PointerEventData eventData)
 {
  image.sprite = sprites[0];
  m_Text.color = Color.black;
 }

 /// <summary>
 /// 鼠标按下事件
 /// </summary>
 /// <param name="eventData"></param>
 public void OnPointerDown(PointerEventData eventData)
 {
  image.sprite = sprites[2];
  m_Text.color = Color.white;
 }

 /// <summary>
 /// 鼠标抬起事件
 /// </summary>
 /// <param name="eventData"></param>
 public void OnPointerUp(PointerEventData eventData)
 {
  image.sprite = sprites[0];
  m_Text.color = Color.black;
 }
}