map object javascript code example

Example 1: map through keys javascript

var myObject = { 'a': 1, 'b': 2, 'c': 3 };

Object.keys(myObject).map(function(key, index) {
  myObject[key] *= 2;
});

console.log(myObject);
// => { 'a': 2, 'b': 4, 'c': 6 }

Example 2: js map on object

import { map } from "ramda"

const double = x => x * 2;

const mappedObject = map(double, {x: 1, y: 2, z: 3}); //=> {x: 2, y: 4, z: 6}

Example 3: object to map javascript

const map = new Map(Object.entries({foo: 'bar'}));

map.get('foo'); // 'bar'

Example 4: javascript map

array.map((item) => {
  return item * 2
} // an example that will map through a a list of items and return a new array with the item multiplied by 2

Example 5: javascript map

const myArray = ['Sam', 'Alice', 'Nick', 'Matt'];

// Appends text to each element of the array
const newArray = myArray.map(name => {
	return 'My name is ' + name; 
});
console.log(newArray); // ['My name is Sam', 'My Name is Alice', ...]

// Appends the index of each element with it's value
const anotherArray = myArray.map((value, index) => index + ": " + value);
console.log(anotherArray); // ['0: Sam', '1: Alice', '2: Nick', ...]

// Starting array is unchanged
console.log(myArray); // ['Sam', 'Alice', 'Nick', 'Matt']

Example 6: javascript map

function listFruits() {
  let fruits = ["apple", "cherry", "pear"]
  
  fruits.map((fruit, index) => {
    console.log(index, fruit)
  })
}

listFruits()

// https://jsfiddle.net/tmoreland/16qfpkgb/3/