Map.prototype.has()
The has() method returns a boolean indicating whether an
element with the specified key exists or not.
Syntax
has(key)Parameters
key- The key of the element to test for presence in the
Mapobject.
Return value
true if an element with the specified key exists in the Map
object; otherwise false.
Examples
Using has()
let myMap = new Map()
myMap.set('bar', "foo")
myMap.has('bar') // returns true
myMap.has('baz') // returns false
Specifications
| Specification |
|---|
| ECMAScript Language Specification (ECMAScript) # sec-map.prototype.has |
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