I find that the value is consistently undefined whenever I attempt to set it within a promise in Angular

Question

I find that the value is consistently undefined whenever I attempt to set it within a promise in Angular

Hi there, I've encountered an issue with my getData() function in accountService.ts. I'm attempting to fetch user data and user account data simultaneously using a zip promise. Although the resolve works correctly and I receive the accurate data, I am facing a problem where the local variables I set to store the returned values always end up as undefined. My intention is to be able to use these variables in other functions.

getData(){
    zip(this.getUser(), this.getAccount()).toPromise().then(data =>{
        this.user = data.values[0];
        console.log(this.user);            
        this.account = data.values[1];
        resolve(data.values[0],data.values[1]);
     });         
}

I'm working with Angular 8 using typescript.

Thank you!

angular typescript angular8

Answer 1

Answer №1

It appears that your function getData() is not returning any values. Here is a suggested approach:

getData(){
    return zip(this.getUser(), this.getAccount()).pipe(
      tap(data => {
        this.user = data.values[0];
        this.account = data.values[1];
      }),
      map(({user, account}) => ({user, account}))
    )       
}

Now, we are returning an

Observable<{user: any, account: any}>

. In the component where this function is utilized, access the values using subscribe:

ngOnInit() {
  this.accountService.getData().subscribe({
    next: data => {
      // Access account using data.account and user using data.user
    }
  })
}

Answer 2

It appears that your function getData() is not returning any values. Here is a suggested approach:

getData(){
    return zip(this.getUser(), this.getAccount()).pipe(
      tap(data => {
        this.user = data.values[0];
        this.account = data.values[1];
      }),
      map(({user, account}) => ({user, account}))
    )       
}

Now, we are returning an

Observable<{user: any, account: any}>

. In the component where this function is utilized, access the values using subscribe:

ngOnInit() {
  this.accountService.getData().subscribe({
    next: data => {
      // Access account using data.account and user using data.user
    }
  })
}

I find that the value is consistently undefined whenever I attempt to set it within a promise in Angular

Answer №1

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