using System;

​

public class Program

{

    public static void Main()

    {

        var lastName1 = "AVeryLongLastName";

        var lastName2 = "3ch";

        var lastName3 = "1";

        var lastName1OldSearchQuick = OldMethod(lastName1, true);

        var lastName1NewSearchQuick = OldMethod(lastName1, true);

        Console.WriteLine(lastName1OldSearchQuick);

        Console.WriteLine(lastName1NewSearchQuick);

        var lastName1OldSearchSlow = OldMethod(lastName1, false);

        var lastName1NewSearchSlow = OldMethod(lastName1, false);

        Console.WriteLine(lastName1OldSearchSlow);

        Console.WriteLine(lastName1NewSearchSlow);

        var lastName2OldSearchQuick = OldMethod(lastName2, true);

        var lastName2NewSearchQuick = OldMethod(lastName2, true);

        Console.WriteLine(lastName2OldSearchQuick);

        Console.WriteLine(lastName2NewSearchQuick);

        var lastName2OldSearchSlow = OldMethod(lastName2, false);

        var lastName2NewSearchSlow = OldMethod(lastName2, false);

        Console.WriteLine(lastName2OldSearchSlow);

        Console.WriteLine(lastName2NewSearchSlow);

        var lastName3OldSearchQuick = OldMethod(lastName3, true);

        var lastName3NewSearchQuick = OldMethod(lastName3, true);

        Console.WriteLine(lastName3OldSearchQuick);

        Console.WriteLine(lastName3NewSearchQuick);

        var lastName3OldSearchSlow = OldMethod(lastName3, false);

        var lastName3NewSearchSlow = OldMethod(lastName3, false);

        Console.WriteLine(lastName3OldSearchSlow);

        Console.WriteLine(lastName3NewSearchSlow);

    }

​

    public static string OldMethod(string lastName, bool quickSearch)

    {

        var lastNameLength = lastName.Length;

        var lastNameSearchText = String.Empty;

        Func<int, string> setLastNameSearchText = length => lastNameLength >= length ? lastName.Substring(0, length) : String.Empty;

        if (quickSearch)

        {

            for (var indx = 3; indx >= 1; indx--)

            {

                lastNameSearchText = String.IsNullOrEmpty(lastNameSearchText) ? setLastNameSearchText(indx) : lastNameSearchText;

            }

        }

        else

        {

            lastNameSearchText = setLastNameSearchText(1);

        }

​

        //find all people in the database for this site with a last name beginning with lastNameSearchText

        return lastNameSearchText += '%';

    }

​

    public static string NewMethod(string lastName, bool quickSearch)

    {

        var lastNameLength = lastName.Length;

        var lastNameSearchText = String.Empty;

        if (quickSearch)

        {

            lastNameSearchText = lastNameSearchText.Substring(0, 3 >= lastNameLength ? 3 : lastNameLength);

        }

        else

        {

            lastNameSearchText = lastNameSearchText.Substring(0, 1);

        }

​

        //find all people in the database for this site with a last name beginning with lastNameSearchText

        return lastNameSearchText += '%';

    }

}