Question

我在authProvider提供程序类中使用此方法：

getUser() {
    return this.afAuth.authState.subscribe(user => {
        return user;
    });
}

我想在不同的课程中订阅它，例如：

this.authProvider.getUser().subscribe(user => console.log(user));

如何在Observable方法中返回getUser()的任何想法？

Answer 1

您的string username = "user"; string password = "password"; string mongoDbAuthMechanism = "SCRAM-SHA-1"; MongoInternalIdentity internalIdentity = new MongoInternalIdentity("admin", username); PasswordEvidence passwordEvidence = new PasswordEvidence(password); MongoCredential mongoCredential = new MongoCredential(mongoDbAuthMechanism, internalIdentity, passwordEvidence); List<MongoCredential> credentials = new List<MongoCredential>() {mongoCredential}; MongoClientSettings settings = new MongoClientSettings(); // comment this line below if your mongo doesn't run on secured mode settings.Credentials = credentials; String mongoHost = "127.0.0.1"; MongoServerAddress address = new MongoServerAddress(mongoHost); settings.Server = address; MongoClient client = new MongoClient(settings); var mongoServer = client.GetDatabase("myDb"); var coll = mongoServer.GetCollection<Employee>("Employees"); // any stubbed out class Employee emp = new Employee() { Id = Guid.NewGuid().ToString(), Name = "Employee_" + DateTime.UtcNow.ToString("yyyy_MMMM_dd") }; coll.InsertOne(emp);已经是可观察的。只需返回您的authState并在另一个函数中订阅即可。在任何其他工作的功能中，您可以使用 RxJS#map 功能。

authState

Answer 2

不要在getUser功能内订阅。只需返回可见的。

getUser() {
    return this.afAuth.authState
}

Answer 3

你可以这样做。然后在您的组件中，调用此函数的组件，您可以订阅此observable。

getUser(): Observable<any> {
    return Observable.create( (observer: Observer<string>) => {
     this.afAuth.authState.subscribe(user => {
        observer.next(user);
    }, (err) => observer.error("error"));
}); 
}

阿什利

Answer 4

您需要将返回类型设置为observable

getUser(): Observable<Type> {
    return this.afAuth.authState;
    });
}

Answer 5

您可以直接返回该函数并在另一个类中订阅它。

  getUser() {
        return this.afAuth.authState();
  }

您可以将observable视为订阅调用的函数。

this.authProvider.getUser().subscribe(user => console.log(user));

如何以角4返回一个Observable？

5 个答案: