map.has

The has() method returns a boolean indicating whether an element with the specified key exists or not.

Syntax

myMap.has(key);

Parameters

key

Required. The key of the element to test for presence in the Map object.

Return value

Boolean

Returns true if an element with the specified key exists in the Map object; otherwise false.

Examples

Using the has method

var myMap = new Map();
myMap.set('bar', "foo");

myMap.has('bar');  // returns true
myMap.has('baz');  // returns false

Specifications

Browser compatibilityUpdate compatibility data on GitHub

See also

• Map
• Map.prototype.set()
• Map.prototype.get()