一些笔记

private void Toggle<T>(ref  T obj)
        {
            List<string> types = Enum.GetNames(obj.GetType()).ToList();
            int index = types.IndexOf(obj.ToString());
            if (index == types.Count - 1)
                index = 0;
            else
                index++;
            string nextstring = types[index];
            Type type = obj.GetType();
            object selected = Enum.Parse(obj.GetType(), nextstring);
            obj = (T)selected;
        }
        //Example 
        private void ChangeEnumValue()
        {
            Toggle<Day>(ref day);
        }