Welcome to my extended series on the S.O.L.I.D. principles in C#. In these five posts, I’ll break down what each principle means, show plenty of code examples, and share best practices for .NET Core applications. Each post focuses on a specific letter—from S to D—so you can deeply understand how to apply them all.

Whether you’re an OOP newcomer or a seasoned developer, these principles will help you write cleaner, more maintainable code that’s a joy to work on.

Jump right in by selecting a part below:

• Part 1: Single Responsibility (S)
• Part 2: Open/Closed (O)
• Part 3: Liskov Substitution (L)
• Part 4: Interface Segregation (I)
• Part 5: Dependency Inversion (D) & Conclusion

I recommend going in order for the most cohesive learning experience. From core concepts of Single Responsibility to the final piece on Dependency Inversion, you’ll see how these principles fit together for more adaptable and robust C# apps.