如何訪問承諾的價值？ - How to access the value of a promise?

問題：

I'm looking at this example from Angular's docs for $q but I think this probably applies to promises in general.我正在查看 Angular 文檔中$q這個例子，但我認爲這可能適用於一般的承諾。 The example below is copied verbatim from their docs with their comment included:下面的例子是從他們的文檔中逐字複製的，包括他們的評論：

promiseB = promiseA.then(function(result) {
  return result + 1;
});

// promiseB will be resolved immediately after promiseA is resolved and its value
// will be the result of promiseA incremented by 1

I'm not clear how this works.我不清楚這是如何工作的。 If I can call .then() on the result of the first .then() , chaining them, which I know I can, then promiseB is a promise object, of type Object .如果我可以對第一個.then()的結果調用.then() ，將它們鏈接起來，我知道我可以，那麼promiseB是一個承諾對象，類型爲Object 。 It is not a Number .它不是一個Number 。 So what do they mean by "its value will be the result of promiseA incremented by 1"?那麼他們所說的“它的值將是 promiseA 加 1 的結果”是什麼意思？

Am I supposed to access that as promiseB.value or something like that?我應該以promiseB.value或類似的方式訪問它嗎？ How can the success callback return a promise AND return "result + 1"?成功回調如何返回承諾並返回“結果 + 1”？ I'm missing something.我錯過了一些東西。

---

解決方案：

參考一： https://en.stackoom.com/question/1zqYo
參考二： https://stackoom.com/question/1zqYo