using System;

using System.Diagnostics;

public class Program

{

    public static void Main()

    {

        const int Repetitions = 100000000;

        Stopwatch sw = new Stopwatch();

        sw.Start();

        for(int i = 0; i < Repetitions; i++) {

            var employee = new Employee();

            var person = (Person)employee;

        }   

        sw.Stop();

        Console.WriteLine(string.Format("Direct cast time: {0}", sw.ElapsedMilliseconds));

​

        sw.Reset(); 

        sw.Start();

        for(int i = 0; i < Repetitions; i++) {

            var employee = new Employee();

            var person = employee as Employee;

        }   

        sw.Stop();

        Console.WriteLine(string.Format("As cast time: {0}", sw.ElapsedMilliseconds));

    }

}

​

public class Person {

    public int Age { get; set; }

    public string Gender {get; set; }

}

​

public class Employee : Person {

    public bool HasRights { get; set; }

    public DateTime LunchTime { get; set; }

}