using System;

using System.Linq;

​

public class Program

{

    public static void Main()

    {

        var cnf = new ThemeConfiguration();

        var tm = new ThemeManager(cnf);

        tm.Configure(config => 

                     { 

                         config.DefaultTheme = "DefaultTheme";

                         config.ThemeDirectory = "Dir1";

                         Console.WriteLine("Called " + config.DefaultTheme);

                     });

        Console.WriteLine("Hello World");

    }

}

​

public class ThemeManager

{

    private readonly IThemeConfiguration _configuration;

    public ThemeManager(IThemeConfiguration configuration)

    {

        configuration.DefaultTheme = "Pink Theme";

        _configuration = configuration;

    }

​

    public void Configure(Action<IThemeConfiguration> configurator)

    {

        configurator(_configuration);

    }

}

​

public interface IThemeConfiguration

{

    string ThemeDirectory

    {

        get;

        set;

    }

​

    string DefaultTheme

    {

        get;

        set;

    }

}

​

public class ThemeConfiguration : IThemeConfiguration

{

    public string ThemeDirectory { get;set;}

    public string DefaultTheme { get;set;}

}