这是一个实验中的功能
此功能某些浏览器尚在开发中，请参考浏览器兼容性表格以得到在不同浏览器中适合使用的前缀。由于该功能对应的标准文档可能被重新修订，所以在未来版本的浏览器中该功能的语法和行为可能随之改变。
The active property of the ServiceWorkerRegistration interface returns a service worker whose ServiceWorker.state is activating or activated. This property is initially set to null.
An active worker controls a ServiceWorkerClient if the client's URL falls within the scope of the registration (the scope option set when ServiceWorkerContainer.register is first called.)
Note: This feature is available in Web Workers.
Syntax
sw = ServiceWorker.active
Value
A ServiceWorker object, if it is currently in an activating or activated state.
Specifications
| Specification | Status | Comment |
|---|---|---|
| Service Workers ServiceWorkerRegistration.active |
Working Draft | Initial definition. |
Browser compatibility
| Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
|---|---|---|---|---|---|
| Basic support | 40.0 | 44.0 (44.0)[1] | 未实现 | ? | 未实现 |
| Available in web workers | (Yes) | 44.0 (44.0)[1] | 未实现 | ? | 未实现 |
| Feature | Android | Firefox Mobile (Gecko) | Firefox OS | IE Mobile | Opera Mobile | Safari Mobile | Chrome for Android |
|---|---|---|---|---|---|---|---|
| Basic support | ? | 44.0 (44.0) | (Yes) | 未实现 | ? | 未实现 | ? |
| Available in web workers | ? | (Yes) | ? | 未实现 | ? | 未实现 | ? |
[1] Service workers (and Push) have been disabled in the Firefox 45 and 52 Extended Support Releases (ESR.)