using System;

​

public interface ICommand

{

    void Execute();

}

​

public class Button

{

    ICommand command;

    public Button(ICommand command)

    {

        this.command = command;

    }

    public void Click()

    {

        command.Execute();

    }

}

​

public class CustomerService

{

    public void AddCustomer() 

    {

        Console.WriteLine("Add Customer");

    }

}

​

public class AddCustomerCommand: ICommand

{

    private CustomerService service;

    public AddCustomerCommand(CustomerService service) 

    {

        this.service = service;

    }

​

    public void Execute() {

        service.AddCustomer();

    }

}

​

​

public class Program

{

    public static void Main()

    {

        var service = new CustomerService();

        var command = new AddCustomerCommand(service);

        var button = new Button(command);

        button.Click();

    }

}