class Program
    {
        static void Main(string[] args)
        {
            MyBooks myBk = new MyBooks(); ;
            for (int i = 0; i < 7; i++)
            {
                myBk[i] = "书籍" + i.ToString();
            }


            for (int j = 0; j <7; j++)
            {
                Console.Write(myBk[j]+"  ");
            }
            Console.ReadKey();
        }
    }

    class MyBooks
    {
       private string [] arr = new string[7];
    
       public string this[int i]
       {
          get { return arr[i]; }
          set { arr[i] = value; }
       }
    }

    class Program
    {
        static void Main(string[] args)
        {
            PrintColor(MyColor.Green);
            Console.ReadKey();

        }

        static void PrintColor(MyColor color)
        {
            switch (color)
            {
                case MyColor.Red:
                    Console.WriteLine("红色");
                    break;
                case MyColor.Green:
                    Console.WriteLine("绿色");
                    break;
                case MyColor.Blue:
                    Console.WriteLine("蓝色");
                    break;
                default:
                    Console.WriteLine("红绿蓝之外的颜色");
                    break;
            }
        }
    }

    enum MyColor
    {
        Red,
        Green,
        Blue
    }