Angular 2+

Question 1

What is name of a special function of class which gets called when object is created and it’s syntax in Typescript?

Answer 1

constructor  —  constructor(){}

Question 2

What are the basic rules of Decorators?

Answer 2

a function which has annotation of @() with optional parameters

Question 3

If you do not know the number of arguments to be passed to function in advance, you should use _______ parameter type.

Answer 3

Rest parameter

Question 4

_____ keyword is used to access class’s member variables and functions inside class member function.

Answer 4

this

Question 5

In Angular, you can pass data from parent component to child component using

Answer 5

@Input()

Question 6

In Angular, you can pass data from child component to parent component using

Answer 6

@Output()

Question 7

Write a syntax for ngFor with <li> example.</li>

Answer 7

<li>
{{item}}
</li>

Question 8

We must import ____________ module to use [(ngModel)].

Answer 8

FormsModule

Question 9

Import ____________ module to use reactive form.

Answer 9

ReactiveFormsModule

Question 10

Write an example to define custom event with Boolean argument with code and passing data to parent component.

Answer 10

objEvent = new EventEmitter();

Question 11

Write a syntax to bind custom CSS class (e.g. highlighted) to a <div> tag.</div>

Answer 11

<div></div>

Question 12

You can create local HTML reference of HTML tag using variable which starts with character

Answer 12

#

Question 13

You can access HTML local reference alias in component’s typescript code using ___________ decorator.

Answer 13

@ViewChild()

Question 14

In template driven form _________ object is created internally whenever we have below code

Answer 14

FormGroup

Question 15

Choose correct form control class name which is set to true when value is modified

Answer 15

.ng-dirty

Question 16

If you provide a service in two components’ “providers” section of @Component decorator, how many instances of service shall get created?

Answer 16

2

Question 17

When you apply ‘pipe’, it changes value of underlying component’s member variable as well.

Answer 17

False

Question 18

In routing, below tag is used to show selected route component dynamically

Question 19

We need to call below method of RouterModule for providing all routes in AppModule

Answer 19

RouterModule.forRoot

Question 20

Angular web application can only be written using Typescript as code behind language

Answer 20

False

Question 21

Fill in blank keyword used to implement inheritance in typescript?
_________

Answer 21

extends

Question 22

Decorator is a class?

Answer 22

False

Question 23

Optional parameter is marked using below syntax:

Answer 23

Fun(name?:string)

Question 24

We can have constructor overloading in Typescript

Answer 24

False

Question 25

In Angular, you can hide/remove HTML element using

Answer 25

*ngIf

Question 26

There can be more than one RootModule in Angular

Answer 26

False

Question 27

ngFor can be applied on any HTML tag e.g.<div> and not just <li></div>

Answer 27

True

Question 28

We can implement two-way data binding using

Answer 28

[(ngModel)]

Question 29

For standard HTML onclick event, we can have below Angular event

Answer 29

(click)

Question 30

EventEmitter data type implementation uses generics concept of Typescript.

Answer 30

True

Question 31

You can update background color of <div> HTML tag using [ngStyle]</div>

Answer 31

True

Question 32

You can have more than one #local variable for an HTML element. E.g.

Answer 32

False

Question 33

Angular custom/built-in Directives cannot listen to standard HTML event raised on their host

Answer 33

False

Question 34

Using Template Driven Form, you can create dynamic form layout

Answer 34

False

Question 35

Choose correct form control class name which is set to true when blur event gets fired on control

Answer 35

.ng-touched

Question 36

Angular Service can be injected at Root Module, Feature Module or Component level

Answer 36

True

Question 37

You can modify DOM of target element using Pipe

Answer 37

False

Question 38

You can define 404 route using below wild card route path

Answer 38

**

Question 39

Below service can be injected in your component to do dynamic route navigation

Answer 39

Router