js map with index code example

Example 1: es6 map usin index

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


const map = array.map((x, index) => {
  console.log(index);
  return x + index;
});

console.log(map);

Example 2: map javascript index

// Arrow function
map((element) => { ... } )
map((element, index) => { ... } )
map((element, index, array) => { ... } )

// Callback function
map(callbackFn)
map(callbackFn, thisArg)

// Inline callback function
map(function callbackFn(element) { ... })
map(function callbackFn(element, index) { ... })
map(function callbackFn(element, index, array){ ... })
map(function callbackFn(element, index, array) { ... }, thisArg)

Example 3: array map javascript

const array1 = [1, 4, 9, 16];

// pass a function to map
const map1 = array1.map(x => x * 2);

console.log(map1);
// expected output: Array [2, 8, 18, 32]

Example 4: array map

const array1 = [1, 4, 9, 16];

// pass a function to map
const map1 = array1.map(x => x * 2);

console.log(map1);
// expected output: Array [2, 8, 18, 32]