WeakMap.prototype.get() - JavaScript | MDN
Try it
const weakmap = new WeakMap();
const object1 = {};
const object2 = {};
weakmap.set(object1, 42);
console.log(weakmap.get(object1));
// Expected output: 42
console.log(weakmap.get(object2));
// Expected output: undefined
Syntax
Parameters
Return value
The value associated with the specified key in the WeakMap object. If the key can't be found, undefined is returned. Always returns undefined if key is not an object or a non-registered symbol.
Examples
Using get()
js
const wm = new WeakMap();
wm.set(window, "foo");
wm.get(window); // Returns "foo".
wm.get("baz"); // Returns undefined.
Specifications
| Specification |
|---|
| ECMAScript® 2027 Language Specification # sec-weakmap.prototype.get |