Unity3D_UGUI判断鼠标或者手指是否点击在UI上

#if UNITY_ANDROID && !UNITY_EDITOR
#define ANDROID
#endif

#if UNITY_IPHONE && !UNITY_EDITOR
#define IPHONE
#endif

using UnityEngine;
using UnityEngine.UI;
using System.Collections;
using UnityEngine.EventSystems;
public class NewBehaviourScript : MonoBehaviour
{

    // Use this for initialization
    void Start()
    {
    }

    void Update()
    {
        if (Input.GetMouseButtonDown(0) || (Input.touchCount > 0 && Input.GetTouch(0).phase == TouchPhase.Began))
        {
            #if IPHONE || ANDROID
                if (EventSystem.current.IsPointerOverGameObject(Input.GetTouch(0).fingerId))
            #else
                if (EventSystem.current.IsPointerOverGameObject())
            #endif
                    Debug.Log("当前触摸在UI上");
                else
                    Debug.Log("当前没有触摸在UI上");
        }
    }
}