using System;

using System.Linq;

using System.Diagnostics;

using System.Collections.Generic;

public class Program

{

    public static IEnumerable<int> _values = GetValues();

    public static void Main()

    {

        int iterations = 100000;

​

        Stopwatch sw;

​

        for (int repeat = 0; repeat < 4; repeat++)

        {

            sw = Stopwatch.StartNew();

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

            {

                var values = _values.ToList();

            }

            Console.WriteLine("ToList: {0} milliseconds", sw.ElapsedMilliseconds);

​

            sw = Stopwatch.StartNew();

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

            {

                var values = _values.ToArray();

            }

            Console.WriteLine("ToArray: {0} milliseconds", sw.ElapsedMilliseconds);

            Console.WriteLine();

        } 

    }

​

    static IEnumerable<int> GetValues()

    {

        for (int i = 0; i < 500; i++)

        {

            yield return i;

        }

    }

}

​

​