Initializing an array of class with certain number of elements in Angular

Question

I am looking for a way to initialize an array of type Passenger which its number of elements is equal to the value of variable count. How can I do it in ngOnInit()???

This is the Passenger model:

export class Passenger {
    constructor(
        public ageCategory: string = '',
        public name: string = '',
        public lastName: string = '',
        public Ssn: string = '',
        public birtDate: NgbDate = new NgbDate(0, 0, 0),
        public passportDate: NgbDate = new NgbDate(0, 0, 0),
        public gender: string = '',
        public passportCountry: string = ''
    ) { }
}

And this the content of home.component.ts:

import { Passenger } from '../../models/passenger';


export class HomeComponent implements OnInit {

  passengers: Passenger[];
  count: number = 5;


  constructor() { }

  ngOnInit() {

  }

}

Bill P · Accepted Answer · 2020-02-09 17:00:14Z

1

Do you mean something like that?:

ngOnInit() {
    this.passengers = new Array<Passenger>(3);
}

To add empty Passenger objects:

passengers: Passenger[] = [];

ngOnInit(){
    for(let i=0;i<this.count;i++){
        let pass= new Passenger();
        this.passengers.push(pass);
    }
}

edited Feb 9, 2020 at 17:00

answered Feb 9, 2020 at 16:29

Bill P

3,61610 gold badges24 silver badges34 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Maryam Heydarian Over a year ago

I have tried this way. But It does not call the constructor of Passenger.

Bill P Over a year ago

So you need to add Passenger objects into the array. You can do like ebove

Kurt Hamilton · Accepted Answer · 2020-02-09 17:46:16Z

1

Call the constructor from within a map:

ngOnInit() {
  this.passengers = new Array(this.count)
    .fill(0)
    .map(_ => new Passenger());
}

edited Feb 9, 2020 at 17:46

answered Feb 9, 2020 at 16:50

Kurt Hamilton

13.7k1 gold badge28 silver badges42 bronze badges

2 Comments

Austaras Over a year ago

this won't work.new Array will generate a array with empty slots and they will be ignored in map

Kurt Hamilton Over a year ago

@Austaras I did not know that. Thanks! Updated my answer for what it's worth.

Collectives™ on Stack Overflow

Initializing an array of class with certain number of elements in Angular

2 Answers 2

2 Comments

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

2 Comments

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related