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• 句法
• 范例
• 规范
• 浏览器兼容性
• 另请参阅
• 相关话题

request 只读特性在 FetchEvent interface returns the Request that triggered the event handler.

This property is non-nullable (since version 46, in the case of Firefox.) If a request is not provided by some other means, the constructor init object must contain a request (see FetchEvent.FetchEvent() )。

句法

var recentRequest = fetchEvent.request;
					

值

A Request 对象。

范例

This code snippet is from the service worker fetch sample ( run the fetch sample live )。 ServiceWorkerGlobalScope.onfetch event handler listens for the fetch event. When fired, pass a promise that back to the controlled page to FetchEvent.respondWith() . This promise resolves to the first matching URL request in the 缓存 object. If no match is found, the code fetches a response from the network.

The code also handles exceptions thrown from the ServiceWorkerGlobalScope.fetch operation. Note that an HTTP error response (e.g., 404) will not trigger an exception. It will return a normal response object that has the appropriate error code set.

self.addEventListener('fetch', function(event) {
  console.log('Handling fetch event for', event.request.url);
  event.respondWith(
    caches.match(event.request).then(function(response) {
      if (response) {
        console.log('Found response in cache:', response);
        return response;
      }
      console.log('No response found in cache. About to fetch from network...');
      return fetch(event.request).then(function(response) {
        console.log('Response from network is:', response);
        return response;
      }).catch(function(error) {
        console.error('Fetching failed:', error);
        throw error;
      });
    })
  );
});
					

规范

规范	状态	注释
服务工作者 The definition of 'request' in that specification.	工作草案	初始定义。

浏览器兼容性

The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request. 更新 GitHub 上的兼容性数据

	桌面						移动
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
request	Chrome Yes	Edge ≤79	Firefox 44	IE 不支持 No	Opera Yes	Safari 不支持 No	WebView Android Yes	Chrome Android Yes	Firefox Android ?	Opera Android Yes	Safari iOS 不支持 No	Samsung Internet Android Yes

图例

完整支持

完整支持

不支持

不支持

兼容性未知 ?

兼容性未知

实验。期望将来行为有所改变。

实验。期望将来行为有所改变。

另请参阅

• 使用服务工作者
• 服务工作者基本代码范例
• ServiceWorker 就绪了吗？
• Promise
• Using web workers

元数据

• 最后修改： Apr 8, 2020

相关话题

1. 服务工作者 API
2. FetchEvent
3. 构造函数

   1. FetchEvent()
4. 特性

   1. client
   2. clientId
   3. isReload
   4. navigationPreload
   5. PreloadRequest
   6. preloadResponse
   7. replacesClientId
   8. request
   9. resultingClientId
5. 方法

   1. respondWith()
6. 继承：

   1. 事件
7. Related pages for Service Workers API

   1. 缓存
   2. CacheStorage
   3. Client
   4. Clients
   5. ExtendableEvent
   6. InstallEvent
   7. Navigator.serviceWorker
   8. NotificationEvent
   9. PeriodicSyncEvent
   10. PeriodicSyncManager
   11. PeriodicSyncRegistration
   12. ServiceWorker
   13. ServiceWorkerContainer
   14. ServiceWorkerGlobalScope
   15. ServiceWorkerRegistration
   16. SyncEvent
   17. SyncManager
   18. SyncRegistration
   19. WindowClient