JavaScript Map
JavaScript Maps is a JavaScript data structure that was added in ECMAScript 6 (ES6). They hold key-value pairs.
Example:
let map1
=
new
Map();
console.log(map1);
// Map {}
JavaScript Map Methods
There are various methods available in JavaScript Map object.
| Method | Description |
|---|---|
| set() | Adds or overwrites a key-value pair to the Map. |
| get() | Returns the value for the given key. |
| delete() | Deletes the element specified from a Map object. |
| has() | Looks whether the Map holds a certain key. |
| forEach() | Invokes a function for every key/value in a Map |
set() Method
In order to add things to a Map, use the set() method:
Example:
let myMap
=
new
Map();
myMap.set('name', 'John');
myMap.set('age', 22);
console.log(myMap.get('name'));
Output:
John
get() Method
The get() method retrieves a value of a key in a Map.
Example:
let myMap
=
new
Map();
myMap.set(1, 'JavaScript');
console.log(myMap.get(1));
Output:
JavaScript