Firestore:snapshotChanges 不是函数 [英] Firestore: snapshotChanges is not a function

问题描述

参考这篇文章，我遇到了一个问题，它说 snapshotChanges is not a function:

In reference to this post, I hit a problem where it says snapshotChanges is not a function:

TypeError: db.collection(...).snapshotChanges is not a function
    at new <anonymous> (index.js:139)
    at Object.instantiate (angular.js:5156)
    at angular.js:11719
    at Object.link (angular-route.js:1251)
    at angular.js:1388
    at Ba (angular.js:11266)
    at p (angular.js:10585)
    at g (angular.js:9832)
    at angular.js:9697
    at angular.js:10111 "<ng-view autoscroll="true" class="ng-scope">"

下面是我的代码:(请注意，有或没有 pipe() 也会遇到同样的错误.)

Below is my code: (Note that with or without pipe() will also hit the same error too.)

var db = firebase.firestore();

        $scope.accounts = db.collection("Accounts").snapshotChanges().pipe(map(actions => {
            return actions.map(a => {
                const data = a.payload.doc.data();
                const id = a.payload.doc.id;
                return { id, ...data };
            });
        }));

在我的 SPA index.html 上，我定义了以下引用:

On my SPA index.html, I have the following references defined:

<script defer src="/__/firebase/6.4.1/firebase-app.js"></script>
  <script defer src="/__/firebase/6.4.1/firebase-auth.js"></script>
  <script defer src="/__/firebase/6.4.1/firebase-firestore.js"></script>
  <script defer src="/__/firebase/6.4.1/firebase-messaging.js"></script>
  <script defer src="/__/firebase/6.4.1/firebase-storage.js"></script> -->
  <script defer src="/__/firebase/init.js"></script>

  <script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.7.8/angular.min.js"></script>
  <script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.7.8/angular-route.min.js"></script>

  <!-- AngularFire -->
  <script src="https://cdn.firebase.com/libs/angularfire/2.3.0/angularfire.min.js"></script>

请问为什么这个错误(snapshotChanges is not a function)仍然出现?我需要它包含doc.id 在我的映射结果中，谢谢！

May I know why this error (snapshotChanges is not a function) still appear? I need it to include the doc.id in my mapping result, thank you!

推荐答案

如果您使用纯 JavaScript SDK 来查询 Firestore，并且想要将侦听器附加到查询，则应该使用 onSnapshot() .

If you're using the plain JavaScript SDK to query Firestore, and you want to attach a listener to a Query, you should be using onSnapshot() for that.

如果您想改用 AngularFire API 并使用 snapshotChanges，这将需要通过它自己的 API(见链接)，这与普通的 JavaScript SDK 不同.

If you want to use the AngularFire API instead and use snapshotChanges, that's going to require a going through its own API (see the link), which is different than the plain JavaScript SDK.

这篇关于Firestore:snapshotChanges 不是函数的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！