Object

⬅️ Execute Program Modern JavaScript

Object

• getters

let userName = 'Amir';
const user = {
  get userName() { return userName}
}
 
// with destructuring
const user = {get name() { return 'Be' + 'tty'; }};
const {name} = user;
name;
 
// Result:
'Betty'
 

setters:

const user = {
  realName: 'Amir',
  set userName(newName) { this.realName = newName; }
};
 
// another example
class User {
  constructor(name) {
    this.names = [name]
  }
   set name(newName) {
    this.names.push(newName);
  }
}

together:

const user = {
  realName: 'Amir',
  get userName() { return this.realName; },
  set userName(newName) { this.realName = newName; },
};
 
user.userName = 'Betty';
[user.realName, user.userName];
 
// Result:
['Betty', 'Betty']

Don’t forget the get or set keyword:

const user = {
  userName: function () { return 'Amir'; }
};
typeof user.userName;
 
// Result:
'function'

Computed properties

const users = [
  {name: 'Amir', loginCount: 5},
  {name: 'Betty', loginCount: 16},
];
 
function loginCount(user) {
    return {[user.name]: user.loginCount}
}