This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the specification changes.
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.
Syntax
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.
Examples
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
| Specification | Status | Comment |
|---|---|---|
| Service Workers The definition of 'CacheStorage' in that specification. |
Working Draft | Initial definition. |
Browser compatibility
| Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
|---|---|---|---|---|---|
| Basic support | 40.0 | 44 (44)[1] | No support | ? | No support |
| Feature | Android | Android Webview | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile | Chrome for Android |
|---|---|---|---|---|---|---|---|
| Basic support | No support | No support | 44.0 (44) | (Yes) | (Yes) | (Yes) | 40.0 |
[1] Service workers (and Push) have been disabled in the Firefox 45 & 52 Extended Support Releases (ESR.)