1. Mounting Phase

• constructor(props): This method is called before the component is mounted. It is typically used to initialize the state and bind event handlers.
• render(): This method returns the JSX that represents the component's UI. It is a pure function and should not contain side effects.
• componentDidMount(): This method is called once the component has been mounted (i.e., inserted into the DOM). It is commonly used to initiate API calls, set up subscriptions, or perform other side effects.

React Hooks Equivalent:

• constructor(props): You no longer need a constructor to initialize state in function components. Instead, you use the useState Hook.

• render(): This is the same as the return statement in the function component.

• componentDidMount(): Replaced by the useEffect Hook with an empty dependency array. This ensures that the effect runs only once after the initial render, similar to componentDidMount.

  
  useEffect(() => {
    // Code here runs once after the component is mounted
  }, []);
  

2. Updating Phase

• render(): This method is called whenever the component's state or props change.
• componentDidUpdate(prevProps, prevState): This method is called after the component has been re-rendered due to changes in props or state. It is often used to perform operations that need to happen when the component updates.

React Hooks Equivalent:

• render(): Again, this corresponds to the return statement of the function component.

• componentDidUpdate(prevProps, prevState): This is replaced by the useEffect Hook without an empty dependency array, where you can specify which props or state variables should trigger the effect.

  
  useEffect(() => {
    // Code here runs after every render
  });
  

  If you want the effect to run only when specific props or state variables change:

  
  useEffect(() => {
    // Code here runs when specificProp or specificState changes
  }, [specificProp, specificState]);
  

3. Unmounting Phase

• componentWillUnmount(): This method is called just before the component is removed from the DOM. It is typically used for cleanup operations such as canceling network requests, clearing timers, or unsubscribing from observables.

React Hooks Equivalent:

• componentWillUnmount(): The useEffect Hook can also handle cleanup by returning a function inside the effect. This function will be called when the component is unmounted.

  
  useEffect(() => {
    return () => {
      // Cleanup code here runs before the component unmounts
    };
  }, []);