public void main()

        {

            //可以存储任何类型的数组

            ArrayList alist = new ArrayList();

            AddData(alist);

            RemoveData(alist);

            UpdateData(alist);

            SearchData(alist);

            OtherFun(alist);

        }

        /// <summary>

        /// 往集合加数据

        /// </summary>

        /// <param name="alist"></param>

        public void AddData(ArrayList alist)

        {

            alist.Add();

            alist.Add(1.1);

            alist.Add("test");

            alist.Add(true);

            alist.Add(new int[] { ,  });  //增加一个数组，增加了1个

            //批量添加

            alist.AddRange(new int[] { ,  });//匹配增加一个数据，增加了2个

            alist.AddRange(new List<string>() { "test1", "test2" });

            alist.Insert(, "test3");

        }

        /// <summary>

        /// 移除集合数据

        /// </summary>

        /// <param name="alist"></param>

        public void RemoveData(ArrayList alist)

        {

            //移除：

            alist.Remove();

            alist.RemoveAt();

            alist.RemoveRange(, );

        }

        /// <summary>

        /// 修改集合数据

        /// </summary>

        /// <param name="alist"></param>

        public void UpdateData(ArrayList alist)

        {

            //修改

            alist[] = ;

            alist.SetRange(, new string[] { "a", "b" });

            //for里面可以修改数据

            for (int i = ; i < alist.Count; i++)

            {

                alist[i] = ;

            }

            //查询:foreach里面，不运行修改、删除、增加集合

            foreach (object val in alist)

            {

                alist[] = ;  //System.InvalidOperationException:“集合已修改；可能无法执行枚举操作。”

            }

        }

        /// <summary>

        /// 查询集合数据

        /// </summary>

        /// <param name="alist"></param>

        public void SearchData(ArrayList alist)

        {

            for (int i = ; i < alist.Count; i++)

            {

            }

            foreach (object val in alist)

            {

            }

            //通过枚举器、迭代器遍历，foreach的底层就是枚举器，也不能里面修改集合

            IEnumerator ie = alist.GetEnumerator();  //一开始ie没有指向，需要movenext才开始指向第一位

            while (ie.MoveNext())

            {

                var val = ie.Current;

            }

        }

        /// <summary>

        /// 集合ArrayList的其他方法

        /// </summary>

        /// <param name="alist"></param>

        public void OtherFun(ArrayList alist)

        {

            //排序

            alist.Sort();     //顺序排序

            alist.Reverse();  //倒叙排序

            //拷贝

            object[] obj = new object[];

            alist.CopyTo(obj);

        }