Design Patterns

Simple repository containing one simple example for all existing patterns in C#.

Creational

Patterns that flexibly create and instantiate objects for you.

• Abstract factory groups object factories that have a common theme.
• Builder constructs complex objects by separating construction and representation.
• Factory method creates objects without specifying the exact class to create.
• Prototype creates objects by cloning an existing object.
• Singleton restricts object creation for a class to only one instance.

Structural

Patterns that define ways to compose objects to obtain new functionality.

• Adapter allows classes with incompatible interfaces to work together.
• Bridge decouples an abstraction from its implementation so that the two can vary independently.
• Composite composes zero-or-more similar objects so that they can be manipulated as one object.
• Decorator dynamically adds/overrides behaviour in an existing method of an object.
• Facade provides a simplified interface to a large body of code.
• Flyweight reduces the cost of creating and manipulating a large number of similar objects.
• Private Class Data restricts exposure of accessor/mutator by limiting their visibility.
• Proxy provides a placeholder for another object to control access, reduce cost, and reduce complexity.

Behavioral

Patterns that specifically concern the communication between objects.

• Chain of responsibility delegates commands to a chain of processing objects.
• Command creates objects which encapsulate actions and parameters.
• Interpreter implements a specialized language.
• Iterator accesses the elements of an object sequentially without exposing its underlying representation.
• Mediator allows loose coupling between classes by being the only class that has detailed knowledge of their methods.
• Memento provides the ability to restore an object to its previous state (undo).
• Observer is a publish/subscribe pattern which allows a number of observer objects to see an event.
• State allows an object to alter its behavior when its internal state changes.
• Strategy allows one of a family of algorithms to be selected on-the-fly at runtime.
• Template method defines the skeleton of an algorithm as an abstract class, allowing its subclasses to provide concrete behavior.
• Visitor separates an algorithm from an object structure by moving the hierarchy of methods into one object.