Answers for "javascript.map"

46

javascript map function

const posts = [
  { id: 1, title: "Sample Title 1", description: "Lorem ipsum dolor sit amet, consectetur adipiscing elit..." },
  { id: 2, title: "Sample Title 2", description: "Lorem ipsum dolor sit amet, consectetur adipiscing elit..." },
  { id: 3, title: "Sample Title 3", description: "Lorem ipsum dolor sit amet, consectetur adipiscing elit..." },
];
// ES2016+
// Create new array of post IDs. I.e. [1,2,3]
const postIds = posts.map((post) => post.id);
// Create new array of post objects. I.e. [{ id: 1, title: "Sample Title 1" }]
const postSummaries = posts.map((post) => ({ id: post.id, title: post.title }));

// ES2015
// Create new array of post IDs. I.e. [1,2,3]
var postIds = posts.map(function (post) { return post.id; });
// Create new array of post objects. I.e. [{ id: 1, title: "Sample Title 1" }]
var postSummaries = posts.map(function (post) { return { id: post.id, title: post.title }; });
Posted by: Guest on October-01-2020
24

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]
Posted by: Guest on November-25-2019
5

how the map function works javascript

const array = [2, 5, 9];
let squares = array.map((num) => num * num);

console.log(array); // [2, 5, 9]
console.log(squares); // [4, 25, 81]
Posted by: Guest on April-07-2020
7

how to use the map method in javascript

const numbers = [1, 2, 3, 4, 5]; 

const bigNumbers = numbers.map(number => {
  return number * 10;
});
Posted by: Guest on April-08-2020
0

map in javascript

const arr = [1, 2, 3, 4, 5, 6];
const mapped = arr.map(el => el + 20);	//[21, 22, 23, 24, 25, 26]
Posted by: Guest on November-17-2021
0

map function in js

let kvArray = [{key: 1, value: 10},
               {key: 2, value: 20},
               {key: 3, value: 30}]

let reformattedArray = kvArray.map(obj => {
   let rObj = {}
   rObj[obj.key] = obj.value
   return rObj
})
// reformattedArray is now [{1: 10}, {2: 20}, {3: 30}],

// kvArray is still:
// [{key: 1, value: 10},
//  {key: 2, value: 20},
//  {key: 3, value: 30}]
Posted by: Guest on June-14-2021

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