Design Patterns in C#

Understanding and effectively applying design patterns is crucial for C# developers who want to create scalable, maintainable, and efficient software. Design patterns encapsulate proven best practices in software design, facilitating communication among developers and ensuring a common approach to problem-solving.

Definition 

Design patterns are typical solutions to common problems in software design. They're like tried-and-tested templates that, once recognized, can be utilized to address frequent design issues in object-oriented software development.

Creational Patterns 

Singleton Pattern: Ensures a class has only one instance and provides a global point to access it. 

Factory Method Pattern: Provides an interface for creating instances of a class, but allows subclasses to change the type of object that will be created. 

Abstract Factory Pattern: Produces families of related or dependent objects without specifying their concrete classes. 

Builder Pattern: Separates the construction of a complex object from its representation. 

Prototype Pattern: Creates a fully cloned copy of an object.

Check out the below tutorials to learn all the creational design patterns in C# with an example:

Singleton Design Pattern in C# with Example
Factory Method Design Pattern in C# with Example
Abstract Factory Design Pattern in C# with Example
Builder Design Pattern in C# with Example
Prototype Design Pattern in C# with Example

Structural Patterns 

Adapter (Wrapper): Convert the interface of a class into another interface that clients expect, allowing classes to work together that couldn't otherwise due to incompatible interfaces. 

Bridge: Decouple an abstraction from its implementation, allowing both to vary independently. 

Composite: Compose objects into tree structures to represent part-whole hierarchies, enabling clients to treat individual objects and compositions uniformly. 

Decorator: Attach additional responsibilities to an object dynamically, offering a flexible alternative to subclassing for extending functionality. 

Facade: Provide a unified interface to a set of interfaces in a subsystem, defining a higher-level interface that makes the subsystem easier to use. 

Flyweight: Use sharing to support large numbers of fine-grained objects efficiently. 

Proxy: Provide a surrogate or placeholder for another object to control access to it.

Check out the below tutorials to learn all the structural design patterns in C# with an example:

Adapter Design Pattern in C# with Example
Bridge Design Pattern in C# with Example
Composite Design Pattern in C# with Example
Decorator Design Pattern in C# with Example
Facade Design Pattern in C# with Example
Flyweight Design Pattern in C# with Example
Proxy Design Pattern in C# with Example

Behavioral Patterns

Chain of Responsibility: Allow an object to pass the request along a chain of potential handlers until an object handles it or the end of the chain is reached. 

Command: Encapsulate a request as an object, thereby allowing for parameterization of clients with different requests, queuing of requests, and logging of operations. 

Interpreter: Provide a representation for a language's grammar and an interpreter to execute the derived representation. 

Iterator (Cursor): Provide a way to access the elements of an aggregate object sequentially without exposing its underlying representation. 

Mediator: Define an object that encapsulates how a set of objects interact, promoting loose coupling by preventing objects from referring to each other explicitly.

Memento: Capture and externalize an object's internal state without violating encapsulation, so the object can be restored to this state later. 

Observer: Define a one-to-many dependency between objects so that when one object changes state, all its dependents are notified and updated automatically. 

State: Allow an object to alter its behavior when its internal state changes, appearing as if the object changed its class. 

Strategy: Define a family of algorithms, encapsulate each one, and make them interchangeable, allowing the algorithm to vary independently from the clients that use it. 

Template Method: Define the skeleton of an algorithm in an operation, deferring some steps to subclasses, letting subclasses redefine certain steps of an algorithm without changing its structure.

Check out the below tutorials to learn all the Behavioral design patterns in C# with an example:

Chain of Responsibility Design Pattern in C# with Example
Command Design Pattern in C# with Example
Interpreter Design Pattern in C# with Example
Iterator Design Pattern in C# with Example
Mediator Design Pattern in C# with Example
Memento Design Pattern in C# with Example
Observer Design Pattern in C# with Example
State Design Pattern in C# with Example
Strategy Design Pattern in C# with Example
Template Method Design Pattern in C# with Example