React Hooks vs Functions made easy (2024)

FAQs

What is the difference between hooks and functions in React? ›

React Hooks are specifically designed to interact with the React component lifecycle and state management. React Hooks can only be used within functional components, whereas JavaScript functions can be used anywhere in your code.

React Hooks offer numerous advantages to developers, including simplified code, improved reusability, easier testing and debugging, and reduced bundle size. By leveraging these benefits, developers can create more efficient, maintainable, and scalable applications.

While class components still have their place, especially in legacy codebases, the versatility and flexibility of Hooks make function components the preferred choice for building modern React applications.

React Hooks were added to solve wrapper hell, huge components, and confusing classes among others that developers faced using class components. However, some of these issues are not connected to React directly, but rather the way native JavaScript classes are designed.

On the other hand, React custom Hooks are functions that encapsulate reusable logic within functional components. They allow stateful logic to be shared without the need for inheritance or prop drilling. Custom Hooks promote cleaner and more composable code, making it easier to share logic across different components.

Only call hooks from React functions: Hooks can be called from React function components or custom hooks, but not from standard JavaScript functions or class components. This rule ensures that every stateful logic in a component's source code is clearly visible.

Class components are still supported by React, but we don't recommend using them in new code. componentDidUpdate(prevProps, prevState, snapshot?) forceUpdate(callback?) setState(nextState, callback?)

Classes are mainly useful to structure larger programs into smaller bits which represent meaningful abstractions, and can potentially be reused.

Functional components provide many advantages over class components in React. They are simpler, more performant, easier to test, work well with the hooks API, and are now the recommended way to write React components.

Don't call Hooks inside loops, conditions, or nested functions. Instead, always use Hooks at the top level of your React function, before any early returns. You can only call Hooks while React is rendering a function component: ✅ Call them at the top level in the body of a function component.

What are the disadvantages of React Hooks? ›

A common pitfall when using React Hooks is the misuse of stale state data. This can occur when we directly reference the state variable in consecutive state updates. Because state updates may be asynchronous, the state variable might not reflect the latest value when it's referenced in successive calls.

React provides a few built-in Hooks like useState . You can also create your own Hooks to reuse stateful behavior between different components. We'll look at the built-in Hooks first. You can learn more about the State Hook on a dedicated page: Using the State Hook.

Don't call Hooks inside loops, conditions, or nested functions. Instead, always use Hooks at the top level of your React function, before any early returns. You can only call Hooks while React is rendering a function component: ✅ Call them at the top level in the body of a function component.

As we can see, Functional components are leaner and more flexible. It's easier to work with state because we have React hooks that help handle state and side effects. If you're building error boundaries, then you should work with Class components.

Hooks are a powerful upgrade coming with React 16.8 and utilize the functional programming paradigm. React, however, also acknowledges the volume of class components already built, and therefore, comes with backward compatibility.