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map.set

The set() method adds or updates an element with a specified key and a value to a Map object.

Syntax

myMap.set(key, value)

Parameters

key
The key of the element to add to the Map object.
value
The value of the element to add to the Map object.

Return value

The Map object.

Examples

Using set()

let myMap = new Map()

// Add new elements to the map
myMap.set('bar', 'foo')
myMap.set(1, 'foobar')

// Update an element in the map
myMap.set('bar', 'baz')

Using the set() with chaining

Since the set() method returns back the same Map object, you can chain the method call like below:

// Add new elements to the map with chaining. 
myMap.set('bar', 'foo')
     .set(1, 'foobar')
     .set(2, 'baz');

Specifications

Browser compatibilityUpdate compatibility data on GitHub

Desktop
Chrome Edge Firefox Internet Explorer Opera Safari
set 38 12 13 11
11
Returns 'undefined' instead of the 'Map' object.
25 8
Mobile
Android webview Chrome for Android Firefox for Android Opera for Android Safari on iOS Samsung Internet
set 38 38 14 25 8 3.0
Server
Node.js
set 0.12
0.12
0.10
Disabled
Disabled From version 0.10: this feature is behind the --harmony runtime flag.

See also

© 2005–2018 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://wiki.developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map/set