#region 做數(shù)據(jù)綁定必須實現(xiàn)的成員

        /// <summary>
        /// 添加元素必須的方法
        /// </summary>
        /// <param name="value"></param>
        /// <returns></returns>
        /// <exception cref="NotImplementedException"></exception>
        public int Add(object? value)
        {
            list.Add(value);
            return list.Count;
            //throw new NotImplementedException();
        }
        public int Count { get { return list.Count; } }
        public object? this[int index] { 
            get { return list[index]; }
            set  { list[index] = value; }
             }
        /// <summary>
        /// 如果要作為DataGridView的數(shù)據(jù)源，必須實現(xiàn)這個屬性
        /// </summary>
        public bool IsReadOnly { get { return false;}
        }
        /// <summary>
        /// 迭代必須的方法
        /// </summary>
        /// <returns></returns>
        /// <exception cref="NotImplementedException"></exception>
        public IEnumerator GetEnumerator()
        {
            return list.GetEnumerator();
            //throw new NotImplementedException();
        }
        #endregion