Map.prototype.keys()

The keys() method of Map instances returns a new map iterator object that contains the keys for each element in this map in insertion order.

Try it

Syntax

js

keys()

Parameters

None.

Return value

Examples

Using keys()

js

const myMap = new Map();
myMap.set("0", "foo");
myMap.set(1, "bar");
myMap.set({}, "baz");

const mapIter = myMap.keys();

console.log(mapIter.next().value); // "0"
console.log(mapIter.next().value); // 1
console.log(mapIter.next().value); // {}

Specifications

Specification
ECMAScript Language Specification
# sec-map.prototype.keys

Browser compatibility

BCD tables only load in the browser

See also