SOLID principles are five guidelines that promote writing clean, maintainable, and testable object-oriented code. Even though they were compatible with class-based development, we can still use them in React functional components. Let’s see how we can apply each principle to React 18 developments.
- S – Single Responsibility Principle (SRP)
- O – Open/ Closed Principle (OCP)
- L – Liskov Substitution Principle (LSP)
- I – Interface Segregation Principle (ISP)
- D – Dependency Inversion Principle (DIP)
S – Single Responsibility Principle (SRP)
Each React component should only have a single, well-defined responsibility.
This makes modularity, easier debugging, and reusability.
Example: Instead of having a single component handling displaying data, user interactions, and styling we can create separate components for each functionality.
O – Open/ Closed Principle (OCP)
The components should be open to extension but should be closed for modifications.
This makes adding new functionality without rewriting existing code.
Example: We can use methods like props, render props, or higher-order components (HOCs) to make components more flexible and easier to extend.
L – Liskov Substitution Principle (LSP)
The child components should be able to use the parent components’ features without causing any unexpected issues or errors.
This makes code reusability and reduces bugs.
Example: If we have a basic `Button` component, other types of buttons (like primary or secondary buttons) should be able to use all the basic button features without any problems. They can also have their own special styles or actions if needed
I – Interface Segregation Principle (ISP)
Large components should be broken down to smaller components into perform for one general purpose.
This makes our code easier to understand and maintain.
Example: Break down a complex form component into smaller components for handling individual input fields, validation logic, and form submission. This improves code organization and reusability.
D – Dependency Inversion Principle (DIP)
Parent (High-level) components should not depend on child (Low-level) components. Instead, they should depend on abstractions like context API, or custom Hooks.
This makes it easier to integrate with different implementations and improve testability
Example: Instead of using a particular data fetching library directly in our components, we can create a custom Hook, context API, or even custom function that describes how data is fetched (for example, fetchData). This allows us to easily switch between different data-fetching libraries without modifying the core component logic.
Happy coding 🙂
