using System;

using System.Diagnostics;

using System.Collections.Generic;

​

public class Program

{   public static void Main()

    {

        var interceptor = new FieldInterceptor();

        var stopwatch = new Stopwatch();

        var iter = 1000000;

        Test(interceptor, 100);

        TestExtension(interceptor, 100);

        stopwatch.Restart();

        Test(interceptor, iter);

        stopwatch.Stop();

        Console.WriteLine($"Total time: {stopwatch.ElapsedMilliseconds}ms");

        stopwatch.Restart();

        TestExtension(interceptor, iter);

        stopwatch.Stop();

        Console.WriteLine($"Total time (extension): {stopwatch.ElapsedMilliseconds}ms");

    }

    private static void Test(IFieldInterceptor interceptor, int iter)

    {

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

        {

            interceptor.Intercept(null);

        }

    }

    private static void TestExtension(IFieldInterceptor interceptor, int iter)

    {

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

        {

            interceptor.Intercept(null, false);

        }

    }

}

​

public interface IFieldInterceptor

{

    void Intercept(object value);

}

​

public class FieldInterceptor : IFieldInterceptor

{

    public void Intercept(object value)

    {

        Intercept(value, false);

    }

​

    public void Intercept(object value, bool setter)

    {

    }

}

​

public static class FieldInterceptorExtensiosn

{

    public static void Intercept(this IFieldInterceptor interceptor, object value, bool setter)

    {

        if (interceptor is FieldInterceptor fieldInterceptor)

        {

            fieldInterceptor.Intercept(value, setter);

        }

​

        interceptor.Intercept(value);

    }

}