Angular Notes

The Angular ViewChildren Decorator and QueryList in Detail

1. @ViewChild and @ViewChildren are local template query mechanism, they can only query component references/nstivr elements of their template and nothing more, this means @ViewChild query can not see inside the templates of child components or parents components, e.g. content projected elements
2. They are aviliable after ngAfterViewInit is called

The Angular Content Projection in Detail

<ng-content></ng-content>

Tha Angular ContentChild Decorator in Detail

Tha Angular ng-template

use ng-container instead, ng-container doesn't create extra elements

Angular Templates as Component Inputs

Tha Angular Directive

• @HostBinding
• @HostListener
• Export as directive instance reference, in which way you can access public properties and methods

Tha Angular Star Syntax

Under the hood

Write custom star syntax ngxUnless

Tha Angular View Encapsulation Under the Hood

:host, ::ng-deep

with ::ng-deep to remove _ngcontent-c1 attributes

Default vs Shadow DOM

• ViewEncapsulation.Emulated(default)

• ViewEncapsulation.None

• ViewEncapsulation.ShadowDom

Angular Injectable Services

Custom Service to fetch data