JavaScript - change value of object inside array

In this article, we would like to show you how to change the value of an object inside an array using JavaScript.

1. Change single property

In this example, we use findIndex() method to get the index of the object we want to change. Then using bracket notation we change the value of the object's name property.

// ONLINE-RUNNER:browser;

const users = [
  { id: 1, name: 'Tom' },
  { id: 2, name: 'Ann' },
  { id: 3, name: 'Mark' },
];

const index = users.findIndex((user) => user.name === 'Ann');

users[index].name = 'Kate';

console.log(JSON.stringify(users[index], null, 4));

2. Change whole object

In this example, we use findIndex() method to get the index of the object we want to change. Then using bracket notation we change the whole object in users array to the replacement.

// ONLINE-RUNNER:browser;

const users = [
  { id: 1, name: 'Tom' },
  { id: 2, name: 'Ann' },
  { id: 3, name: 'Mark' },
];

const replacement = { id: 2, name: 'Kate' };

const index = users.findIndex((user) => user.name === 'Ann');

users[index] = replacement;

console.log(JSON.stringify(users[index], null, 4));

See also

1. JavaScript - find object in array

References

1. Array.prototype.findIndex() - JavaScript | MDN
2. Property accessors - JavaScript | MDN