set Method (WeakMap) (JavaScript)

Adds a new element to a WeakMap object.


weakmapObj.set(key, value)  


Required. A WeakMap object.

Required. An object representing the key of the element to add. This must be an object reference.

Required. The value of the element to add.

Property Value/Return Value

Returns the WeakMap object that contains the new key/value pair.


If you add a value to the collection using an existing key, the new value will replace the old value.


The following example shows how to add members to a WeakMap object.

var dog = {  
    breed: "yorkie"  

var cat = {  
    breed: "burmese"  

var wm = new WeakMap();  
wm.set(dog, "fido");  
wm.set(cat, "pepper");  


Supported in the Internet Explorer 11 standards document mode. Also supported in Store apps (Windows 8.1 and Windows Phone 8.1). See Version Information.
Not supported in the following document modes: Quirks, Internet Explorer 6 standards, Internet Explorer 7 standards, Internet Explorer 8 standards, Internet Explorer 9 standards, Internet Explorer 10 standards. Not supported in Windows 8.