unity silder 点击小圆点执行命令

 EventTrigger trigger = mySlider.gameObject.GetComponent<EventTrigger>();
        EventTrigger.Entry entry = new EventTrigger.Entry();
        // 鼠标点击事件
        entry.eventID = EventTriggerType.EndDrag;
        entry.callback = new EventTrigger.TriggerEvent();
        entry.callback.AddListener(OnClick);
        trigger.triggers.Add(entry);

 private void OnClick(BaseEventData pointData) {
        Debug.Log("Button Clicked. EventTrigger..");      
    }