WeakMap.prototype.has()

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

Syntax

has(key)

Parameters

• key
  • : Required. The key of the element to test for presence in the WeakMap object.

Return value

• Boolean
  • : Returns true if an element with the specified key exists in the WeakMap object; otherwise false.