Object Destructuring

Destructuring assignment simplifies the process of assigning array values and object properties to variables.

Example

// Create an Object
const person = {
firstName: “John”,
lastName: “Doe”,
age: 50,
eyeColor: “blue”
};

// Destructuring Assignment
let { firstName, age } = person;

Note:

When destructuring an object, the variable names must match the corresponding object keys. The order of the keys does not matter.

Array Destructuring

Destructuring assignment allows for easy extraction of array values and object properties into variables.

Example

// Create an Array
const fruits = [“Banana”, “Orange”, “Apple”, “Mango”];

// Destructuring Assignment
let [fruit1, fruit2] = fruits;

The Spread (…) Operator

The … operator spreads an iterable (such as an array) into individual elements.

Example

const q1 = [“Jan”, “Feb”, “Mar”];
const q2 = [“Apr”, “May”, “Jun”];
const q3 = [“Jul”, “Aug”, “Sep”];
const q4 = [“Oct”, “Nov”, “May”];

const year = [...q1, ...q2, ...q3, ...q4];

The … operator can be used to spread an iterable into individual arguments in a function call.

Example

const numbers = [23,55,21,87,56];
let maxValue = Math.max(...numbers);