C#的索引器

using System;
using System.Collections;
using System.Collections.Generic;
using System.IO;

namespace codeTest
{

    class Program
    {

        static void Main(string[] args)
        {
            IndexTest indexname = new IndexTest();
            indexname[0] = "0";
            indexname[1] = "1";
            indexname[2] = "2";
            indexname[3] = "3";
            indexname[4] = "4";
            indexname[5] = "5";
            indexname[6] = "6";
            indexname[7] = "7";
            indexname[8] = "8";
            indexname[9] = "9";
            for (int i = 0; i < 10; i++)
            {
                Console.WriteLine(indexname[i]);
            }

            Console.WriteLine(indexname["1"]);
            Console.WriteLine(indexname["2"]);
            Console.WriteLine(indexname["6"]);
            IndexTest1 indextest1 = new IndexTest1();
            Console.WriteLine(indextest1[1]);
            Console.WriteLine(indextest1[2]);
            Console.WriteLine(indextest1[3]);
            Console.ReadLine();
        }

        public class IndexTest
        {
            string[] indexName;
            public IndexTest()
            {
                indexName = new string[10] { "", "", "", "", "", "", "", "", "", "" };
            }

            public string this[int index]
            {
                get
                {
                    string tmp;
                    if (index >= 0 && index <= 10)
                    {
                        tmp = indexName[index];
                    }
                    else
                    {
                        tmp = "";
                    }
                    return tmp;
                }
                set
                {
                    if (index >= 0 && index <= 10)
                    {
                        indexName[index] = value;
                    }
                }
            }

            public int this[string name]
            {
                get
                {
                    int index = 0;
                    while (index < indexName.Length)
                    {
                        if (indexName[index] == name)
                        {
                            return index;
                        }
                        index++;
                    }

                    return -1;
                }
            }

        }

        public interface IIndexTest
        {
            int this[int index]
            {
                get;
                set;
            }
        }

        public class IndexTest1 : IIndexTest
        {
            int[] array = new int[5] { 1, 2, 3, 4, 5 };

            public int this[int index]
            {
                get
                {
                    return array[index];
                }
                set
                {
                    array[index] = value;
                }
            }
        }

    }

}