Polymorphism isn’t just a language feature, it’s a way to build systems that are easier to extend, change, and maintain. Learn how polymorphism powers design patterns like Template Method, Strategy, and Visitor in C#.
TL;DR: Inheritance isn’t evil, it’s appropriate when you need polymorphism without runtime behavior swapping Use inheritance for stable “is-a” relationships where behavior is intrinsic to the type Composition adds unnecessary complexity when the behavior won’t change at runtime Good examples for inheritance include domain models, DTO hierarchies, and static polymorphic behavior Design principles are guidelines, not rules, the right solution depends on your specific context Don’t overengineer with composition when inheritance provides a simpler, clearer solution You’ve probably heard the advice: “Favor composition over inheritance.” But does that mean inheritance is always bad? No, and here’s when it still shines. ...
Discover how composition helps you follow the SOLID principles in C#. See practical examples for each principle, learn why composition is more flexible than inheritance, and get actionable tips for writing robust, testable, and maintainable code.
Discover why composition is often a better choice than inheritance in C#. This article explains the drawbacks of deep inheritance, demonstrates how to use composition for flexible and maintainable code, and provides practical tips for applying these principles in real-world projects. Includes code examples and guidance for testable, scalable software design.
Discover how to use encapsulation and information hiding to write safer, more maintainable C# code. This article covers practical examples, common pitfalls, and modern C# features for protecting internal state and exposing clear, stable interfaces.
Discover how polymorphism makes C# code more flexible and future-proof. See how to replace switch statements with interfaces, add new features without breaking existing code, and write modular, testable business logic. Includes practical examples and actionable best practices for modern C# development.
TL;DR: Cohesion: How closely related a class’s responsibilities are. Aim for high cohesion, each class should do one focused job well. Coupling: How dependent one class is on others. Aim for low coupling to make code easier to change, test, and maintain. Low coupling high cohesion lead to clean, modular, and maintainable object-oriented designs. Introduction to Cohesion vs Coupling in Software Engineering Ever stared at a massive class file with hundreds of lines of code and thought, “What is this thing even supposed to do?” I sure have. That confusion usually points to problems with cohesion and coupling in software engineering, two concepts that might sound academic but actually make the difference between code you want to work with and code you want to run away from. ...
TL;DR: DIP (Dependency Inversion Principle): High-level modules should not depend on low-level modules; both depend on abstractions. DI (Dependency Injection): A technique to supply dependencies from outside a class, improving testability and flexibility. IoC (Inversion of Control): A broader concept where control of object creation and dependency resolution is delegated to a container or framework. Together, they enable decoupled, maintainable, and testable applications. DIP is a design principle, DI is a pattern, IoC is the overarching concept. Introduction If you’ve ever been in a job interview for a software developer position, chances are you’ve been asked to explain the difference between DIP, DI, and IoC. I know I have, and the first time I was asked, I definitely stumbled through my answer! ...
TL;DR: Encapsulation: Keep data and logic together, hide internals behind clean interfaces Abstraction: Expose only what matters, hide the messy details Inheritance: Reuse common behavior by deriving from base classes Polymorphism: Write flexible code that works across types sharing a contract Introduction Ever wondered why most modern programming languages are object-oriented? It’s not just a trend; OOP completely changed how we think about building software. Object-Oriented Programming (or OOP, as we’ll call it) burst onto the scene in the 1990s and turned traditional programming on its head. Before OOP came along, most developers wrote procedural code, essentially a series of steps for the computer to follow, like a cooking recipe. While that worked for simpler programs, it became unwieldy as software grew more complex. ...
TL;DR - SOLID principles SRP: one class, one reason to change OCP: extend without modifying LSP: subclasses must behave like base types ISP: keep interfaces focused DIP: depend on abstractions, not implementations Introduction This SOLID tutorial in C# walks through each principle: SRP, OCP, LSP, ISP, and DIP, with practical code, refactoring examples, and real-world scenarios. If you’ve been coding for a while, you’ve probably heard of SOLID. It’s a set of five design principles that Robert C. Martin (better known as “Uncle Bob”) came up with back in the early 2000s. Since then, these ideas have become pretty much essential knowledge for anyone writing object-oriented code. ...