using System;

using System.Collections.Generic;

using System.Diagnostics;

using System.Linq;

​

namespace app

{

    public class Program

    {

        [Flags]

        public enum Test

        {

            Flag1 = 1,

            Flag2 = 2,

            Flag3 = 4,

            Flag4 = 8

        }

        static int num = 0;

        static Random rand;

        public static void Main(string[] args)

        {

            int seed = (int)DateTime.UtcNow.Ticks;

​

            var st1 = new SpeedTest(delegate

            {

                Test t = Test.Flag1;

                t |= (Test)rand.Next(1, 9);

                if (t.HasFlag(Test.Flag4))

                    num++;

            });

​

            var st2 = new SpeedTest(delegate

            {

                Test t = Test.Flag1;

                t |= (Test)rand.Next(1, 9);

                if (HasFlag(t , Test.Flag4))

                    num++;

            });

            var st3 = new SpeedTest(delegate

            {

                Test t = Test.Flag1;

                if (t ==Test.Flag1)

                    num++;

            });

            var st4 = new SpeedTest(delegate

            {

                Test t = Test.Flag1;

                //try   {   

                if (t==Test.Flag4)

                    num++;

                //} catch {

                //  num=0;

                //}

            });

​

            rand = new Random(seed);

            st1.Test();

            rand = new Random(seed);

            st2.Test();

            st3.Test();

            st4.Test();

            Console.WriteLine("Random to prevent optimizing out things {0}", num);

            Console.WriteLine("HasFlag: {0}ms {1}ms {2}ms", st1.Min, st1.Average, st1.Max);

            Console.WriteLine("Bitwise: {0}ms {1}ms {2}ms", st2.Min, st2.Average, st2.Max);

            Console.WriteLine("Equality: {0}ms {1}ms {2}ms", st3.Min, st3.Average, st3.Max);

            Console.WriteLine("Equality not found: {0}ms {1}ms {2}ms", st4.Min, st4.Average, st4.Max);

            //Console.ReadLine();

        }

        static bool HasFlag(Test flags, Test flag)

        {

            return (flags & flag) != 0;

        }

    }

    class SpeedTest

    {

        public int Iterations { get; set; }

​

        public int Times { get; set; }

​

        public List<Stopwatch> Watches { get; set; }

​

        public Action Function { get; set; }

​

        public long Min { get { return Watches.Min(s => s.ElapsedMilliseconds); } }

​

        public long Max { get { return Watches.Max(s => s.ElapsedMilliseconds); } }

​

        public double Average { get { return Watches.Average(s => s.ElapsedMilliseconds); } }

​

        public SpeedTest(Action func)

        {

            Times = 10;

            Iterations = 100000;

            Function = func;

            Watches = new List<Stopwatch>();

        }

​

        public void Test()

        {

            Watches.Clear();

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

            {

                var sw = Stopwatch.StartNew();

                for (int o = 0; o < Iterations; o++)

                {

                    Function();

                }

                sw.Stop();

                Watches.Add(sw);

            }

        }

    }

}