c#索引器详解示例

{
    get{//获得属性的代码}                                                
    set{ //设置属性的代码}
}

class Z
{
        //可容纳100个整数的整数集
        private long[] arr = new long[100];
        //声明索引器
        public long this[int index]
        {
            get
            { //检查索引范围
                if (index < 0 || index >= 100)
                {
                    return 0;
                }
                else
                {
                    return arr[index];
                }
            }
            set
            {
                if (!(index < 0 || index >= 100))
                {
                    arr[index] = value;
                }
            }
   }

Z  z=new  z();
z[0]=100;
z[1]=101;
Console.WriteLine(z[0]);

public interface IAddress
{
string this[int index]{get;set;}
string Address{get;set;}
string Answer();
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace suoyin
{
    class Program
    {
        static void Main(string[] args)
        {
            int[] values = { 3,5,7,9};
            int i = values[1];

            Person p1 = new Person();
            p1[1] = "小明";
            Console.WriteLine(p1[1]+p1[2]);

            Console.WriteLine(p1["tom",3,9]);//索引也可以重载。
            Console.ReadKey();
        }
    }

    class Person
    {
        private string FirstName="大毛";
        private string SecondName="二毛";

        public string this[string name, int x, int y]
        {
            get
            {
                return name + x + y;
            }
        }
        public string this[int index]//中括号里的就是索引。
        {
            get
            {
                if (index == 1)
                {
                    return FirstName;
                }
                else if (index == 2)
                {
                    return SecondName;
                }
                else
                {
                    throw new Exception("这是个错误的序号啊亲！");
                }
            }
            set
            {
                if (index == 1)
                {
                    FirstName = value;
                }
                else if (index == 2)
                {
                    SecondName = value;
                }
                else
                {
                    throw new Exception("这是个错误的序号啊亲！");
                }
            }
        }
    }
}