Behavioural Patterns

Behavioural Patterns focus on how objects cooperate and pass work along, using techniques like commands or observers to reduce tight links and simplify testing.

Chain of Responsibility Pattern: Leave Request Approval Chain

Explains the Chain of Responsibility Pattern in C# using a leave approval analogy to show how requests are passed until someone handles them.

Command Pattern: Voice Assistant (e.g. Alexa, Siri)

Explains the Command Pattern in C# using the voice assistant analogy to show how requests are wrapped as objects and executed separately.

Interpreter Pattern: Language Translator

Explains the Interpreter Pattern in C# using the language interpreter analogy, showing how structured input can be evaluated using grammar rules.

Iterator Pattern: Elevator Stopping at Each Floor

Explains the Iterator Pattern in C# using the elevator and floor analogy to show how to move through collections without knowing their internal structure.

Mediator Pattern: Air Traffic Controller

Explains the Mediator Pattern in C# using an air traffic controller analogy, showing how to decouple objects by routing communication through a central mediator.

Memento Pattern: Game Save Feature

Explains the Memento Pattern in C# using the save game feature analogy, showing how to capture and restore object state safely.

Null Object Pattern: Default Voicemail Greeting

Explains how the Null Object Pattern avoids null checks using a default voicemail analogy.

Observer Pattern: YouTube Subscriber

Explains the Observer Pattern in C# using the YouTube subscription analogy, including how to implement subjects and observers.

State Pattern: Phone Modes - Silent, Vibrate, Normal

Explains the State Pattern in C# using the phone mode analogy, showing how internal state determines behaviour and how to isolate logic with state classes.

Strategy Pattern: Navigation App Routes

Explains the Strategy Pattern in C# using the navigation app analogy, showing how to swap interchangeable algorithms without changing business logic.

Template Method Pattern: Baking a Cake from a Recipe

Explains the Template Method Pattern in C# using the cake recipe analogy, showing how to define a structure with customisable steps.

Visitor Pattern: Visitors at a Company Office

Explains the Visitor Pattern in C# using a company visitor analogy, where different types of visitors interact with departments without modifying them.

Specification Pattern: Club Entry Rules

The Specification Pattern is a design approach in C# for defining business rules as modular, reusable objects that can be easily combined.

Pipeline / Middleware Pattern: Assembly Line in a Factory

The Pipeline (Middleware) Pattern is a flexible design approach in C# that allows data or requests to pass through a chain of reusable steps, where each step can modify, inspect, or terminate the flow.