using System;

using System.Collections.Generic;

​

public class Program

{

    public static void Main()

    {

        var c = new CollectionClass();

        var watch = System.Diagnostics.Stopwatch.StartNew();

        for (var i = 0; i < 10000; i++)

            c.Test1();

        watch.Stop();

        Console.WriteLine("Test1:" + watch.ElapsedMilliseconds);

​

        watch = System.Diagnostics.Stopwatch.StartNew();

        for (var i = 0; i < 10000; i++)

            c.Test2();

        watch.Stop();

        Console.WriteLine("Test2:" + watch.ElapsedMilliseconds);

​

        watch = System.Diagnostics.Stopwatch.StartNew();

        for (var i = 0; i < 10000; i++)

            c.Test3();

        watch.Stop();

        Console.WriteLine("Test3:" + watch.ElapsedMilliseconds);

​

        watch = System.Diagnostics.Stopwatch.StartNew();

        for (var i = 0; i < 10000; i++)

            c.Test4();

        watch.Stop();

        Console.WriteLine("Test4:" + watch.ElapsedMilliseconds);

    }

}

​

internal class CollectionClass

{

    public List<string> ListData { get; set; }

​

    public void Test1()

    {

        ListData = new List<string>();

        string[] names = { "Matt", "Joanne", "Robert" };

        foreach (var item in names)

            ListData.Add(item);

    }

​

    public void Test2()

    {

        string[] names = { "Matt", "Joanne", "Robert" };

        ListData = new List<string>();

        ListData.AddRange(names);

    }

​

    public void Test3()

    {

        ListData = new List<string>();

        ListData.Add("Matt");

        ListData.Add("Joanne");

        ListData.Add("Robert");

    }

​

    public void Test4()

    {

        ListData = new List<string>(){ "Matt", "Joanne", "Robert" };

    }

}