Search code examples
javascriptarraysangularjavascript-objectsangular-arrays

Copy array of Objects in angular 2


I have two array called 'persons' and 'persons2', The 'persons2' array would to be copy of 'persons' array, But the problem is when I copy it, and I want to change the second array, the first array is also changing. This is my code:

  export class AppComponent {

  persons = [
    {
      name:'David',
      lname:'Jeu'
    }
  ];

  persons2=[...this.persons];

  constructor(){
      console.log(this.persons[0]);
      this.persons2[0].name='Drake';
      console.log(this.persons[0]);

      console.log(this.persons2[0]);
  }

}

Solution

  • But the problem is when I copy it, and I want to change the second array, the first array is also changing

    That is because the objects inside both the arrays are sharing same reference. To perform a deep copy try the following :

    let persons2 = person.map(x => Object.assign({}, x));
    

    Or

    let person2 = JSON.parse(JSON.stringify(person));