How to deep copy in angular 4 without using JQuery functions? [duplicate]

Question

I have an hero array that I show it in list by *ngFor and when I Click on one of it element it copied on new variable and new variable go to input by tow way binding . my heroClass:

export class Hero {
    id: number;
    name: string;
  } 

my hero-mock list:

import { Hero } from './heroClass';

export const HEROES: Hero[] = [
  { id: 11, name: 'Mr. Nice' },
  { id: 12, name: 'Narco' },
  { id: 13, name: 'Bombasto' },
  { id: 14, name: 'Celeritas' },
  { id: 15, name: 'Magneta' },
  { id: 16, name: 'RubberMan' },
  { id: 17, name: 'Dynama' },
  { id: 18, name: 'Dr IQ' },
  { id: 19, name: 'Magma' },
  { id: 20, name: 'Tornado' }
];

My hero component:

   import { Component, OnInit } from '@angular/core';
    import { Hero } from '../hero';
    import { HEROES } from '../mock-heroes';

    @Component({
      selector: 'app-heroes',
      templateUrl: './heroes.component.html',
      styleUrls: ['./heroes.component.css']
    })
    export class HeroesComponent implements OnInit {

      heroes = HEROES;

      selectedHero: Hero;


      constructor() { }

      ngOnInit() {
      }

      onSelect(hero: Hero): void {
        this.selectedHero = hero;
      }
    }

heroes.component.html

<h2>My Heroes</h2>
<ul class="heroes">
  <li *ngFor="let hero of heroes"
    [class.selected]="hero === selectedHero"
    (click)="onSelect(hero)">
    <span class="badge">{{hero.id}}</span> {{hero.name}}
  </li>
</ul>

<div *ngIf="selectedHero">

  <h2>{{ selectedHero.name | uppercase }} Details</h2>
  <div><span>id: </span>{{selectedHero.id}}</div>
  <div>
    <label>name:
      <input [(ngModel)]="selectedHero.name" placeholder="name">
    </label>
  </div>

</div>

the problem is when i select one hero and show copy of it on text input and change it the hero of list that is selected changing too.

in angularjs 1 I prevent from this issue by using angular.copy() built in method but in angular 2 i have to create new of Hero and attributing propery of selectedHero to main hero:

  selectedHero: new Hero();
onSelect(hero: Hero): void {
        this.selectedHero.name = hero.name;
         this.selectedHero.id= hero.id;
      }

is there other way to deep copy in angular 2 without using jquery or js function and above way?

Answer 1

This is pretty hacky in my opinion, but it does work.

this.selectedHero = JSON.parse(JSON.stringify(hero));

For Shallow Copy: You can use the spread operator:

this.selectedHero = {...hero};
let {...example} = hero;

Answer 2

Use lodash's cloneDeep function.

---

There's nothing in Angular for deep cloning an object because it is not Angular's concern to provide such a function.