WeakMap.prototype.get()
 The get() method returns a specified element from a WeakMap object. 
Try it
Syntax
get(key)
Parameters
 key  Required. The key of the element to return from the WeakMap object.  Return value
 The element associated with the specified key in the WeakMap object. If the key can't be found, undefined is returned. Examples
Using the get() method
const wm = new WeakMap();
wm.set(window, 'foo');

wm.get(window); // Returns "foo".
wm.get('baz');  // Returns undefined.
Specifications

Specification
ECMAScript Language Specification # sec-weakmap.prototype.get

Browser compatibility




Desktop
Mobile
Server



Chrome
Edge
Firefox
Internet Explorer
Opera
Safari
WebView Android
Chrome Android
Firefox for Android
Opera Android
Safari on IOS
Samsung Internet
Deno
Node.js



get
36
12

6
Before Firefox 38, this method threw a TypeError when the key parameter was not an object. However, the ES2015 specification specifies to return undefined instead. Furthermore, WeakMap.prototype.get accepted an optional second argument as a fallback value, which is not part of the standard. Both non-standard behaviors are removed in version 38 and higher.

11
23
8
37
36

6
Before Firefox 38, this method threw a TypeError when the key parameter was not an object. However, the ES2015 specification specifies to return undefined instead. Furthermore, WeakMap.prototype.get accepted an optional second argument as a fallback value, which is not part of the standard. Both non-standard behaviors are removed in version 38 and higher.

24
8
3.0
1.0

0.12.0
0.10.0



See also
 WeakMap WeakMap.prototype.set() WeakMap.prototype.has() 

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Last modified: Sep 5, 2022, by MDN contributors


    
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