angularjs - 再次解决已解决的 promise

Question

我正在使用 AngularJS 的 $q，当我创建一个 promise 并且该 promise 已经解决时，它可以再次解决吗？我不知道这是否可能，但如果不可能，有没有办法让我可以一次又一次地解决相同的 promise 。我正在考虑使用通知方式，但我不知道是否还有其他方法可以做到这一点。

Answer 1

来自Mastering Web Application Development with Angularjs, by Kozlowski and Bacon ，第 3 章“与后端服务器通信”，“使用 $q 的 Promise API”部分:

A promise that was resolved or rejected once can't change its state.

There is only one chance of providing promised results. In other words it is not possible to:

• Resolve a rejected promise
• Resolve an already resolved promise with a different result
• Reject a resolved promise
• Reject a rejected promise with a different rejection reason

Those rules are rather intuitive.For example, it wouldn't make much sense if we could be called back with the information that there are problems with a pizza order delivery after a pizza was successfully delivered (and probably eaten!).

如果您提供更多代码，并且我们可以更好地理解您想要做什么，我们也许能够为您提供帮助。