weakMap.get

weakMap.get

get() 方法返回  WeakMap 指定的元素。

语法

wm.get(key

参数

key必须。 想要从 WeakMap 获取的元素的键。

返回值

返回与指定键相关联的值,如果 WeakMap 对象找不到这个键则返回 undefined。

示例

使用get 方法

var wm = new WeakMap( wm.set(window, 'foo' wm.get(window // Returns "foo". wm.get('baz' // Returns undefined.

规范

SpecificationStatusComment
ECMAScript 2015 (6th Edition, ECMA-262)The definition of 'WeakMap.prototype.get' in that specification.StandardInitial definition.
ECMAScript Latest Draft (ECMA-262)The definition of 'WeakMap.prototype.get' in that specification.Draft

浏览器兼容性

FeatureChromeEdgeFirefox (Gecko)Internet ExplorerOperaSafari
Basic support36(Yes)6.0 (6.0)11237.1

FeatureAndroidEdgeFirefox Mobile (Gecko)IE MobileOpera MobileSafari Mobile
Basic supportNo support(Yes)6.0 (6.0)No supportNo support8