angular-basic-elements

Question 1

Structural directives

Answer 1

Those are responsible for the page layout. Just like media in html. Structural directives: NgIf, NgFor, NgSwitch.

Question 2

Dependency injection

Answer 2

Design pattern which requires instance of class rather than create it.

Question 3

Routing

Answer 3

Single page applications with navigation for changing views. 
Application need to have 2 componets at least. And module for routing.

Question 4

Guard Rouing

Answer 4

It checks if the user have the permission to acces the module

Question 5

CLI command in angular to create new component

Answer 5

ng g c name-of-component

Question 6

NgClass directive what for is used ?

Answer 6

We can add html element classes by using NgClass directive:
----- html -----
 PressME
----- ts -----
elementClasses= {
dimmed : true, 
special : false, 
hidden : true
}

button will belong to classes: dimmed, hidden

Question 7

NgStyle what for is used?

Answer 7

NgStyle is used for manipulating styles of the element, the syntax is similar to the NgClass.

Question 8

NgModel what is used for ?

Answer 8

Ng model allows us to change data in the html elements, the syntax is more complex, because we need to make [(ngModel)]

Question 9

ngIf

Answer 9

*ngIf = “isActive”

directive ngIf allows to show element if the variable is true

Question 10

ngFor

Answer 10

*ngFor = “let item of items”

ng for allows to get acces for iterative element in some set using elementwise for.

Question 11

ngSwitch case

Answer 11

the name tell us what it does, but the syntax is ugly

<div>
‹div *ngSwitchCase="'Bob'"›Hi dad</div>

<div>Hi Mom
<div>Hi friend</div></div>

Question 12

How to make routing?

Answer 12

1. make app-routing.module
2. import router in app routing module
3. define routes in module
4. set the imports, exports
5. use the routerLink
6. use

Question 13

How to pass data during routing?

Answer 13

By ActivatedRouter