Single-Responsibility-Principle

TL;DR: SRP means each class or module should have only one reason to change. Split validation, data access, and business logic into separate classes. SRP improves maintainability, testability, and scalability. Use C# 12 features like primary constructors and records for clean separation. Avoid “God” classes and mixing unrelated responsibilities. SRP is the foundation for applying other SOLID principles. Refactor large classes by extracting focused components and using dependency injection. The Single Responsibility Principle gets misunderstood more than any other SOLID principle. It’s not about doing one thing, it’s about having one reason to change. When your class changes for multiple business reasons, you’ve violated SRP and created a maintenance nightmare. ...

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. ...