using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

namespace NetTest

{

public class TestIndexClass

{

public void Test()

{

TempRecord tempRecord = new TempRecord();

// Use the indexer's set accessor

tempRecord[3] = 58.3F;

tempRecord[5] = 60.1F;

// Use the indexer's get accessor

for (int i = 0; i < 10; i++)

{

// This example validates the input on the client side. You may

// choose to validate it in the class that implements the indexer, and throw an

// exception or return an error code in the case of invalid input.

if (i < tempRecord.Length)

{

System.Console.WriteLine("Element #{0} = {1}", i, tempRecord[i]);

}

else

{

System.Console.WriteLine("Index value of {0} is out of range", i);

}

}

//Uncomment this code to see how the .NET Framework handles indexer exceptions

//try

//{

//    System.Console.WriteLine("Element #{0} = {1}", tempRecord[tempRecord.Length]);

//}

//catch (System.ArgumentOutOfRangeException e)

//{

//    System.Console.WriteLine(e);

//}

DayCollection week = new DayCollection();

System.Console.WriteLine(week["Fri"]);

System.Console.WriteLine(week["Made-up Day"]);

}

}

class TempRecord

{

// Array of temperature values

private float[] temps = new float[10] { 56.2F, 56.7F, 56.5F, 56.9F, 58.8F,

61.3F, 65.9F, 62.1F, 59.2F, 57.5F };

// Auto-Implemented Property

System.DateTime date { get; set; }

// To enable client code to validate input

// when accessing your indexer.

public int Length

{

get { return temps.Length; }

}

// Indexer declaration.

// Input parameter is validated by client

// code before being passed to the indexer.

public float this[int index]

{

get

{

return temps[index];

}

set

{

temps[index] = value;

}

}

}

//C# 并不将索引类型限制为整数。例如，对索引器使用字符串可能是有用的。通过搜索集合内的字符串并返回相应的值，可以实现此类索引器。

//由于访问器可被重载，字符串和整数版本可以共存。

class DayCollection

{

string[] days = { "Sun", "Mon", "Tues", "Wed", "Thurs", "Fri", "Sat" };

// This method finds the day or returns -1

private int GetDay(string testDay)

{

int i = 0;

foreach (string day in days)

{

if (day == testDay)

{

return i;

}

i++;

}

return -1;

}

// The get accessor returns an integer for a given string

public int this[string day]

{

get

{

return (GetDay(day));

}

}

}

}