A list,
Angular is a platform and framework for building client applications in HTML and TypeScript. It is named after the HTML element tag symbol <, which indicates sharp corners.
Note: The pre-2.0 version of Angular, called AngularJS, was created in 2009 by Misko Hevery and others and later acquired by Google.
Since the 2.0 release in 2015, Angular has changed dramatically, rewritten in TypeScript as a completely different framework without the JS name.
Second, the component
1. Component composition and creation
@Component decorator, CSS selector, HTML templates, CSS styles, Typescript classes that define behavior
2. Component life cycle
Instantiate component classes, destroy views and subviews, change detection, lifecycle hooks
Lifecycle hook execution order:
(1) OnChanges() : called when the input property of the component changes
(2) ngOnInit() : called after the component’s data is ready, before the component view is initialized
(3) ngDoCheck() : it is called every time data change detection is carried out, very frequently
NgAfterContentInit () : called when Angular projects external content into the component view or directive view
(5) ngAfterContentChecked() : Called whenever Angular has checked something projected into a component or directive
NgAfterViewInit () : called after Angular has initialized the component view and its children, or the view containing the directive
(7) ngAfterViewChecked() : Called whenever Angular finishes checking for changes to component views and subviews or views that contain this directive
(8) ngOnDestroy() : called and cleaned every time Angular destroys a directive/component