javascript destructuring function arguments code example

Example 1: javascript function destructuring

function f() {
  return [1, 2];
}

let a, b; 
[a, b] = f(); 
console.log(a); // 1
console.log(b); // 2

Example 2: object destructuring example

const hero = {
  name: 'Batman',
  realName: 'Bruce Wayne',
  address: {
    city: 'Gotham'
  }
};

// Object destructuring:
const { realName, address: { city } } = hero;
city; // => 'Gotham'

Example 3: js object destructuring with defaults

// Taken from top stack overflow answer

const { dogName = 'snickers' } = { dogName: undefined }
console.log(dogName) // what will it be? 'snickers'!

const { dogName = 'snickers' } = { dogName: null }
console.log(dogName) // what will it be? null!

const { dogName = 'snickers' } = { dogName: false }
console.log(dogName) // what will it be? false!

const { dogName = 'snickers' } = { dogName: 0 }
console.log(dogName) // what will it be? 0!

Example 4: js destructuring explained

const { identifier } = expression;

Example 5: array destructuring in javascript

const array = ['ismail', 'sulman'];
// array destructuring
const [firstElement, secondElement] = array;
console.log(firstElement, secondElement);
const secondArray = ['ismail', 'naeem', 'Mr', 1];
const [firstEl, secondEl, ...array1] = secondArray;
console.log(firstEl, secondEl, array1);

Example 6: javascript destructuring

const classDetails = {
  strength: 78,
  benches: 39,
  blackBoard:1
}

const {strength:classStrength, benches:classBenches,blackBoard:classBlackBoard} = classDetails;

console.log(classStrength); // Outputs 78
console.log(classBenches); // Outputs 39
console.log(classBlackBoard); // Outputs 1