React JS Lecture #24 | What is Component Updating Lifecycle Methods
When working with React, it is important to understand the different lifecycle methods that are available for components. One set of lifecycle methods that are particularly useful are the updating methods, which are called when a component is re-rendered due to changes in its props or state.
Component Updating Lifecycle Methods
When a component is updated, the following methods are called in a specific order:
- shouldComponentUpdate(nextProps, nextState) – This method is called before the component is about to update. It is used to determine if the component should re-render or not. By default, this method returns true, meaning the component will re-render. You can override this method to implement custom logic for determining whether the component should update or not.
- componentWillUpdate(nextProps, nextState) – This method is called just before the component is updated. It is often used to perform any necessary cleanup or preparation before the update.
- render() – This method is called to render the updated component based on the new props and state.
- componentDidUpdate(prevProps, prevState) – This method is called after the component has been updated. It is often used to perform any necessary post-update actions, such as making API calls or updating the DOM.
It is important to note that the updating lifecycle methods are not always called in every update. The shouldComponentUpdate method is used to determine if the component should re-render, and if it returns false, the updating lifecycle methods will not be called.
By understanding and utilizing the component updating lifecycle methods in React, you can have more control over how your components re-render and optimize the performance of your application.