In Angular, lifecycle hooks are special methods that provide insights into the lifecycle of components and directives, allowing developers to perform custom operations at specific stages. Here’s a detailed overview of the lifecycle hooks available for both components and directives:
Lifecycle Hooks for Components
constructor(): This is the JavaScript class constructor for the component. It is used to inject dependencies but not for any Angular-specific logic.
ngOnChanges(): Called before ngOnInit() and whenever one or more data-bound input properties change. The method receives a SimpleChanges object containing current and previous property values[1][2][3].
ngOnInit(): Called once, after the first ngOnChanges(). It is used for initial component initialization and setting up the component after Angular first displays the data-bound properties[1][2][3].
ngDoCheck(): Called during every change detection run, allowing you to implement custom change detection logic or do something on every check[1][2][3].
ngAfterContentInit(): Called after Angular projects external content into the component’s view. It is invoked only once after the first ngDoCheck()[1][2][3].
ngAfterContentChecked(): Called after the content projected into the component has been checked, and it is called after every subsequent ngDoCheck()[1][2][3].
ngAfterViewInit(): Called after Angular initializes the component's views and child views. It is called once after the first ngAfterContentChecked()[1][2][3][12].
ngAfterViewChecked(): Called after the component's views and child views have been checked. It is invoked after every ngAfterContentChecked()[1][2][3].
