Unity获取鼠标滚轮信息有以下一些方法：

1、使用Input.GetAxis(“Mouse ScrollWheel”)来获取鼠标滚轮的信息，如：

 //法一：float scrollWheelInput = Input.GetAxis("Mouse ScrollWheel");if (scrollWheelInput > 0f){Debug.Log("向上滚动鼠标滚轮");}else if (scrollWheelInput < 0f){Debug.Log("向下滚动鼠标滚轮");}

2、使用mouseScrollDelta变量，如：

 //法二：float scrollWheelInput1 = Input.mouseScrollDelta.y;if (scrollWheelInput1 > 0f){Debug.Log("向上滚动鼠标滚轮");}else if (scrollWheelInput1 < 0f){Debug.Log("向下滚动鼠标滚轮");}

3、假如我们想只在UGUI上滚动鼠标滚轮才获取信息，可以使用一个专门的接口：IScrollHandler，实现的方法是：

    public void OnScroll(PointerEventData eventData){throw new System.NotImplementedException();}

该函数的参数PointerEventData具有很多相关的数据：

    public class PointerEventData : BaseEventData{public List<GameObject> hovered;public PointerEventData(EventSystem eventSystem);public bool useDragThreshold { get; set; }public bool dragging { get; set; }public InputButton button { get; set; }public float pressure { get; set; }public float tangentialPressure { get; set; }public float altitudeAngle { get; set; }public float azimuthAngle { get; set; }public float twist { get; set; }public Vector2 radius { get; set; }public Vector2 radiusVariance { get; set; }public bool fullyExited { get; set; }public bool reentered { get; set; }public Camera enterEventCamera { get; }public Camera pressEventCamera { get; }public GameObject pointerPress { get; set; }public Vector2 scrollDelta { get; set; }public int clickCount { get; set; }public float clickTime { get; set; }[Obsolete("Use either pointerCurrentRaycast.worldNormal or pointerPressRaycast.worldNormal")]public Vector3 worldNormal { get; set; }public GameObject pointerEnter { get; set; }public GameObject lastPress { get; }public GameObject rawPointerPress { get; set; }public GameObject pointerDrag { get; set; }public RaycastResult pointerCurrentRaycast { get; set; }public RaycastResult pointerPressRaycast { get; set; }public GameObject pointerClick { get; set; }public int pointerId { get; set; }public Vector2 position { get; set; }public Vector2 delta { get; set; }public Vector2 pressPosition { get; set; }[Obsolete("Use either pointerCurrentRaycast.worldPosition or pointerPressRaycast.worldPosition")]public Vector3 worldPosition { get; set; }public bool eligibleForClick { get; set; }public bool IsPointerMoving();public bool IsScrolling();public override string ToString();public enum InputButton{Left = 0,Right = 1,Middle = 2}public enum FramePressState{Pressed = 0,Released = 1,PressedAndReleased = 2,NotChanged = 3}}

其中，scrollDelta属性与上面方法1/2的数据一样。所以我们可以这样实现方法以获取滚轮信息：

//法三：public void OnScroll(PointerEventData eventData){if (eventData.scrollDelta.y > 0f){Debug.Log("向上滚动鼠标滚轮");}else if (eventData.scrollDelta.y < 0f){Debug.Log("向下滚动鼠标滚轮");}}

使用法三，需要注意的是：只有我们把控制脚本放在相应的UGUI物体上才有效，或者放在Canvas下对所有UGUI有效。

但使用该方法的好处是：我们可以通过UGUI实现在指定获取滚轮信息。