CacheStorage.delete()

The delete() method of the CacheStorage interface finds the Cache object matching the cacheName, and if found, deletes the Cache object and returns a Promise that resolves to true. If no Cache object is found, it returns false.

语法

caches.delete(cacheName).then(function(true) {
  //your cache is now deleted
});

Returns

a Promise that resolves to true if the Cache object is found and deleted, and false otherwise.

Parameters

cacheName

The name of the cache you want to delete.

实例

In this code snippet we wait for an activate event, and then run a waitUntil() block that clears up any old, unused caches before a new service worker is activated. Here we have a whitelist containing the name of the cache we want to keep. We return the keys of the caches in the CacheStorage object using CacheStorage.keys, then check each key to see if it is in the whitelist. If not, we delete it using delete().

this.addEventListener('activate', function(event) {
  var cacheWhitelist = ['v2'];
  event.waitUntil(
    caches.keys().then(function(keyList) {
      return Promise.all(keyList.map(function(key) {
        if (cacheWhitelist.indexOf(key) === -1) {
          return caches.delete(key);
        }
      }));
    })
  );
});

Specifications

Browser compatibility

[1] Service workers (and Push) have been disabled in the Firefox 45 & 52 Extended Support Releases (ESR.)

See also

• Using Service Workers
• Cache
• WorkerGlobalScope.caches