js object.assign code example

Example 1: javascript assign

const obj = { a: 1 };
const copy = Object.assign({}, obj);
console.log(copy); // { a: 1 }

Example 2: javascript object.assign

const target = { a: 1, b: 2 };
const source = { b: 4, c: 5 };

const returnedTarget = Object.assign(target, source);

console.log(target);
// expected output: Object { a: 1, b: 4, c: 5 }

console.log(returnedTarget);
// expected output: Object { a: 1, b: 4, c: 5 }

Example 3: object assign

The Object.assign() method copies all enumerable own properties from one or more source objects to a target object. It returns the target object.
const target = { a: 1, b: 2 };
const source = { b: 4, c: 5 };

const returnedTarget = Object.assign(target, source);

console.log(target);
// expected output: Object { a: 1, b: 4, c: 5 }

console.log(returnedTarget);
// expected output: Object { a: 1, b: 4, c: 5 }

Example 4: object.assign react js

'use strict';

// Merge an object
let first = {name: 'Tony'};
let last = {lastName: 'Stark'};
let person = Object.assign(first, last);
ChromeSamples.log(person);
// {name: 'Tony', lastName: 'Stark'}
ChromeSamples.log(first);
// first = {name: 'Tony', lastName: 'Stark'} as the target also changed

// Merge multiple sources
let a = Object.assign({foo: 0}, {bar: 1}, {baz: 2});
ChromeSamples.log(a);
// {foo: 0, bar: 1, baz: 2}

// Merge and overwrite equal keys
let b = Object.assign({foo: 0}, {foo: 1}, {foo: 2});
ChromeSamples.log(b);
// {foo: 2}

// Clone an object
let obj = {person: 'Thor Odinson'};
let samp = {person: 'ashok'}; 
let clone = Object.assign({}, obj, samp);
ChromeSamples.log(clone);

// {person: 'Thor Odinson'}

Example 5: copy an object with object.assign

// We want to update status property value to 'online'
const data = {
  user: 'CamperBot',
  status: 'offline',
  friends: '732,982',
};

// Object.assign takes in a target object (1st parameter) and source objects 
// (rest of the parameter list). Source object properties are mapped to the 
// target object (which is usually empty). Any matching properties are 
// overwritten by the source objects
const newObject = Object.assign({}, data, {status: 'online'})

console.log(newObject)
/* 
  {
    user: 'CamperBot',
    status: 'online',
    friends: '732,982',
  }
*/

Example 6: Object.assign()

const obj1 = {
				a: 5,
                b: 2
                }
const obj2 = Object.assign({a:6 d:7}, obj1);

console.log(obj2);
// output:  { a: 5 , b: 2, d:7}