Template Method Pattern C# simple example

HotelBookingTemplate.cs

public abstract class HotelBookingTemplate
{
    // Template Method
    public void BookRoom()
    {
        SelectRoom();
        ProcessPayment();
        ApplyDiscount();
        SendBookingConfirmation();
    }

    // Common for all subclasses
    private void SelectRoom()
    {
        Console.WriteLine("Room selected.");
    }

    // Must be implemented by subclasses
    protected abstract void ProcessPayment();

    // Hook (optional override by subclasses)
    protected virtual void ApplyDiscount() { }

    // Common for all bookings
    private void SendBookingConfirmation()
    {
        Console.WriteLine("Booking confirmation sent.");
    }
}

// Standard booking without discount
public class StandardBooking : HotelBookingTemplate
{
    protected override void ProcessPayment()
    {
        Console.WriteLine("Processing payment at standard rate.");
    }
}

// Premium booking with discount
public class PremiumBooking : HotelBookingTemplate
{
    protected override void ProcessPayment()
    {
        Console.WriteLine("Processing payment at premium rate.");
    }

    protected override void ApplyDiscount()
    {
        Console.WriteLine("Applying 10% discount for premium customers.");
    }
}

// Client Code
class Program
{
    static void Main(string[] args)
    {
        Console.WriteLine("Standard Booking Process:");
        HotelBookingTemplate standardBooking = new StandardBooking();
        standardBooking.BookRoom();

        Console.WriteLine("\nPremium Booking Process:");
        HotelBookingTemplate premiumBooking = new PremiumBooking();
        premiumBooking.BookRoom();
    }
}