public class IDisponseTest : IDisposable
    {
        private bool isReadyDisposed = false;

        ~IDisponseTest()
        {
            //析構函數調用時不釋放托管資源，因為交由GC進行釋放
            Disponse(false);
        }

        public void Dispose()
        {
            //用戶手動釋放托管資源和非托管資源
            Disponse(true);
            //用戶已經釋放了托管和非托管資源，所以不需要再調用析構函數
            GC.SuppressFinalize(this);

            //如果子類繼承此類時，需要按照如下寫法進行。
            //try
            //{
            //    Disponse(true);
            //}
            //finally
            //{
            //    base.Disponse();
            //}
        }

        public virtual void Disponse(bool isDisponse)
        {
            //isReadyDisposed是控制只有第一次調用Disponse才有效才需要釋放托管和非托管資源
            if (isReadyDisposed)
                return;
            if (isDisponse)
            {
                //析構函數調用時不釋放托管資源，因為交由GC進行釋放
                //如果析構函數釋放托管資源可能之前GC釋放過，就會導致出現異常

                //托管資源釋放
            }
            //非托管資源釋放
            isReadyDisposed = true;
        }
    }

class Program
    {
        static void Main(string[] args)
        {
            CubeEnum cubelist = new CubeEnum(50);
            foreach(Cube cube in cubelist)
            {
                Console.WriteLine("立方體長：" + cube.Length + ",寬" + cube.Width + ",高" + cube.Height);
            }
            Console.Read();
        }
    }
    //立方體，長、寬、高
    public class Cube
    {
        public int Length { get; set; }
        public int Width { get; set; }
        public int Height { get; set; }
    }
    /// <summary>
    /// 立方體迭代集合，繼承了IEnumerable和IEnumerator
    /// </summary>
    public class CubeEnum : IEnumerable, IEnumerator
    {
        //索引
        public int Index { get; set; }
        //立方體集合
        public Cube[] cubelist { get; set; }
        //初始化立方體集合
        public CubeEnum(int count)
        {
            this.Index = -1;
            cubelist = new Cube[count];
            for (int i = 0; i < count; i++)
            {
                cubelist[i] = new Cube();
                cubelist[i].Length = i * 10;
                cubelist[i].Width = i * 10;
                cubelist[i].Height = i * 10;
            }
        }
        //實現IEnumerable的 GetEnumerator() 方法獲得IEnumerator對象
        public IEnumerator GetEnumerator()
        {
            return (IEnumerator)this;
        }
        //當前Cube立方體
        public object Current
        {
            get { return cubelist[Index]; }
        }
        //往下一步移動
        public bool MoveNext()
        {
            Index++;
            if (Index < cubelist.Length)
            {
                return true;
            }
            return false;
        }
        //重置索引
        public void Reset()
        {
            Index = -1;
        }
    }