Map.prototype.has()

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

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Syntax

myMap.has(key);

Parameters

key

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

Return value

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 compatibility

See also

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