using System;

using System.Collections;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World, {0}, {1}", 1, 2);

        var dp = new DataProvider();        

        var pageDp = new DataProviderPaging();

        IList records = pageDp.GetEvenNumbers();

        var i = 0;

        foreach(var record in records)

        {

            Console.WriteLine("Record: {0}, Index: {1}", record, i++);  

        }

        records = pageDp.GetEvenNumbers(11, 20);        

        i = 0;

        foreach(var record in records)

        {

            Console.WriteLine("Record: {0}, Index: {1}", record, i++);  

        }

    }

}

​

public class DataProvider

{

    int dataSize = 100;

    IList records = new List<int>();

    public DataProvider()

    {

        GenerateData();

    }

    private IList GenerateData()

    {

        // records: 1, 2, 3, 4, 5, 6

        // index:   0, 1, 2, 3, 4, 5

        for(var i=0; i < dataSize; i++)

        {

            records.Add(i + 1);

        }

        return records;

    }

    public virtual List<int> GetEvenNumbers()

    {

        var evenNumbers = new List<int>();

        foreach(int record in records)

        {

            if ((record % 2) == 0)

            {

                evenNumbers.Add(record);

            }

        }

        return evenNumbers;

    }

}

​

public class DataProviderPaging : DataProvider

{

    public DataProviderPaging() : base()

    {   

    }

​

    public List<int> GetEvenNumbers(int startIndex, int pageSize)

    {

        var evenNumbers = base.GetEvenNumbers();

        List<int> records = evenNumbers.GetRange(startIndex, pageSize);

        return records;

    }

}

​

​

​

​

​

​

​

​

​

​