Difference Between Class Component and Functional Component in React

In this article we are going to show you Difference Between Class Component and Functional Component in React

Class Components:

• Class components are JavaScript classes that extend the React.Component class or its subclass, and define a render() method to return the component’s JSX (JavaScript XML) markup.
• They have a state object and lifecycle methods, such as componentDidMount() and componentDidUpdate(), that allow developers to control the behavior of the component at different stages of its lifecycle.
• Class components are recommended when the component needs to have state, or when the component needs to use lifecycle methods.

Functional Components:

• Functional components are JavaScript functions that take props as input and return the component’s JSX markup.
• They do not have a state object, and therefore they do not have lifecycle methods.
• Functional components are recommended when the component does not need to have state, and when the component’s behavior is simple and straightforward.

Some key differences between Class Components and Functional Components are:

1. Syntax: Class components are defined as JavaScript classes, while functional components are defined as JavaScript functions.
2. State: Class components have a state object, while functional components do not. State allows components to store and manipulate data over time, and is useful when the component needs to change based on user interaction or other factors.
3. Lifecycle methods: Class components have lifecycle methods, which are methods that are automatically called at different stages of the component’s lifecycle. Functional components do not have lifecycle methods, which can make them simpler and more lightweight.
4. Performance: Functional components are generally considered to be more performant than class components, because they do not have the overhead of state and lifecycle methods. However, this performance difference is usually only noticeable in very large applications or in cases where the component is rendering frequently.

Overall, both class components and functional components have their own advantages and use cases, and developers should choose the type of component that best fits their needs.