有没有办法“观察”IndexedDB记录，以便在更改时作出响应？(Is there a way to “watch” an IndexedDB record so I can respond when

有没有办法“观察”IndexedDB记录，以便在更改时作出响应？(Is there a way to “watch” an IndexedDB record so I can respond when it's been changed?)

我正在构建一个使用IndexedDB在本地存储数据的Angular + TypeScript应用程序。

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我有一个Angular指令，它将scope变量的值设置为从IndexedDB请求返回的一些数据。 这非常简单，并执行如下操作：

指令A：

// getGroup() is making the requests to IndexedDB: this.dataService.getGroup().then((groupOne) => { this.scope.items = groupOne.items; });

指令B：

groupOne.items.push("a new item"); this.dataService.updateGroup(groupOne).then(() => { // groupOne has been changed! // how can I let Directive A know about this, so Directive A can update its scope.items? });

Directive A:

// getGroup() is making the requests to IndexedDB: this.dataService.getGroup().then((groupOne) => { this.scope.items = groupOne.items; });

Directive B:

groupOne.items.push("a new item"); this.dataService.updateGroup(groupOne).then(() => { // groupOne has been changed! // how can I let Directive A know about this, so Directive A can update its scope.items? });

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Of course, Directive A does not know about the changes Directive B made to groupOne unless it does another request. And therefore, my view is "static".

I know I could wrap Directive A's IndexedDB request into an interval and be checking for updates, but that seems like a strange way to solve this problem.

Is there a way with IndexedDB to be notified of this change? Is there something Angular provides that could help with this (something similar to $scope.$watch()) ?

最满意答案

还没有一种方法可以用纯粹的IndexedDB来做到这一点，但它正在被原型化。 这个名字是“观察者”。 如果你喜欢，你可以尝试使用polyfill 。

There is not yet a way to do this with pure IndexedDB but it is being prototyped. The name is "Observers". You can try to use the polyfill if you are so inclined.