The has() method of Map instances returns a boolean indicating whether an element with the specified key exists in this map or not.

Syntax

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 has()

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

console.log(myMap.has("bar")); // true
console.log(myMap.has("baz")); // false

Specifications

Browser compatibility

See also

• Map
• Map.prototype.set
• Map.prototype.get