[JavaScript Demo] Maps in JavaScript ES6

This example demonstrates how to use maps in JavaScript ES6

by Rahul Saraswat

HTML

<!-- Please press ctrl-shift-i to see output in browser console window. -->

JavaScript

//A Map is an unordered list of key-values pairs where the key AND the value can be of any type.

var mapDemo = new Map();
mapDemo.set('name', 'Rahul');						//set function to store data as key/value pair
mapDemo.set(5, 50);
var obj = {};
mapDemo.set(obj, 'JavaScript Object');		//storing JavaScript object as a key

console.log(mapDemo.get('name'));					//get function to retrieve value from collection
console.log(mapDemo.get(5));
console.log(mapDemo.get(obj));						//Passed 'obj' (above created) as a key to get value
console.log(mapDemo.has('name'));				//'has' function to check if key exists or not, returns true
console.log(mapDemo.has(obj));					//returns true
console.log(mapDemo.size);						//'size' property gives number of stored key/values pairs
console.log(mapDemo.delete(obj));			//'delete' function to delete data from collection using key. It returns true, if item deleted. otherwise false.
//After deleting one item, lets check if it exists or not
console.log(mapDemo.has(obj));					//returns false

console.log(mapDemo.clear());			//'clear' function removes all key/value pairs from map
console.log(mapDemo.size);				//return 0