ServiceWorkerContainer.controller

实验性: 这是一项实验性技术
在将其用于生产之前，请仔细检查浏览器兼容性表格。

当状态为activated 时， ServiceWorkerContainer 接口的只读属性 controller 返回一个 ServiceWorker 对象（与 ServiceWorkerRegistration.active 返回的对象是同一个）。当页面强制刷新 (Shift + refresh) 或不存在 active worder 时，该属性返回 null 。

语法

var myController = navigator.serviceWorker.controller;

值

一个ServiceWorker对象。

示例

js

if ('serviceWorker' in navigator) {
  // Do a one-off check to see if a service worker's in control.
  if (navigator.serviceWorker.controller) {
    console.log('This page is currently controlled by:',
      navigator.serviceWorker.controller);
  } else {
    console.log('This page is not currently controlled ' +
      'by a service worker.');
  }
} else {
  console.log('Service workers are not supported.');
}

规范

Specification
Service Workers
# navigator-service-worker-controller

浏览器兼容性

BCD tables only load in the browser