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Map.prototype.set()

The set() method of Map instances adds or updates an entry in this map with a specified key and a value.

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Syntax

js
set(key, value)

Parameters

key

The key of the element to add to the Map object. The key may be any JavaScript type (any primitive value or any type of JavaScript object).

value

The value of the element to add to the Map object. The value may be any JavaScript type (any primitive value or any type of JavaScript object).

Return value

The Map object.

Examples

Using set()

js
const 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:

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

Specifications

Browser compatibility

Desktop Mobile Server
Chrome Edge Firefox Opera Safari Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet WebView Android Deno Node.js
set 38 12 13 25 8 38 14 25 8 3.0 38 1.0 0.12.0

See also

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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map/set