Angular calls the lifecycle hook methods in the following sequence after creating a component/directive in Angular 6 by calling its constructor:

  • ngOnChanges()
    This responds when Angular re-sets data-bound input properties.
  • ngOnInit()
    Used to initialize the directive/component after Angular first displays the data-bound properties while setting the directive/component's input properties.
  • ngDoCheck()
    Called during every change detection run, immediately after ngOnChanges() and ngOnInit() to detect and act upon changes that Angular won’t do on its own
  • ngAfterContentInit()
    Called once after the first ngDoCheck() to respond after Angular projects external content into the component’s/directive’s view
  • ngAfterContentChecked()
    Called after the ngAfterContentInit() and every subsequent ngDoCheck() to respond after Angular checks the projected content.
  • ngAfterViewInit()
    Called once after the first ngAfterContentChecked() to respond after Angular validates the component and it’s child views.
  • ngAfterViewChecked()
    Called after the ngAfterViewInit() and after every subsequent ngAfterContentChecked().
  • ngOnDestroy()
    Called just before Angular destroys the directive/component to avoid memory leaks by effective cleanup just before destroying the directives.
sequence of Angular lifecycle hooks
In the Angular 6 interview question, it is highly recommended to answer the question with the correct sequence by explaining every point. Doing this will increase your chance to get hired.
BY Best Interview Question ON 10 Nov 2020