js for in or for of code example

Example 1: javascript for of

const array = ['hello', 'world', 'of', 'Corona'];

for (const item of array) {
  console.log(item);
}

Example 2: javascript for of

const numbers = [1,2,3,4];

for(const item of numbers){
  console.log(item);
}

Example 3: for in and for of in js

Object.prototype.objCustom = function () {}; 
Array.prototype.arrCustom = function () {};

let iterable = [3, 5, 7];
iterable.foo = "hello";

for (let i in iterable) {
  console.log(i); // logs 0, 1, 2, "foo", "arrCustom", "objCustom"
}

for (let i of iterable) {
  console.log(i); // logs 3, 5, 7
}

Example 4: for in and for of in js

const iterable = [10, 20, 30];

for (const value of iterable) {
  console.log("fef"+value);
}
// 10
// 20
// 30