I am working with Angular, I have issues with asynchronous function call.
async ngOnInit() {
this.a = new A();
await this.a.method_A();
this.b = new B(this.a);
this.b.method_B(this.a.data);
}
export class A {
data;
async method_A() {
observable$.subscribe((data) => { this.data = data });
}
}
method_A is an asynchronous function, so it has to be ensured that after the method_A is completed, b has to be instantiated and the method_B has to be invoked. So, I used await/async like above, but I still find that instance b is created before method_A is completed. Is there a way for those steps to be performed sequentially?
async method_A() {
observable$.subscribe((data) => { this.data = data });
}
method_A doesn't wait for observable$ to emit. What is observable$, BTW? Does it emit only once? If so, you can easily convert it to the async-await pattern with
async method_A() {
const data = await observable$.toPromise();
this.data = data;
}
or, as toPromise is deprecated or will be soon,
async method_A() {
const data = await firstValueFrom(observable$);
this.data = data;
}
(And if observable$ emits more than once, I suggest ditching the async-await pattern and just using RxJS).
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