how to use the forkjoin function from the rxjs library in javascript

The forkJoin function from the RxJS library is used to combine multiple Observables into one, by waiting for all of them to complete. When all the Observables have completed successfully, they will be combined into an array and passed to the forkJoin function's subscriber.

Here's an example of how to use forkJoin in JavaScript:

index.tsx
import { forkJoin } from 'rxjs';

const observable1 = // create an observable
const observable2 = // create another observable

forkJoin([observable1, observable2]).subscribe(
  ([result1, result2]) => {
    // do something with the results
    console.log(result1, result2);
  },
  (error) => {
    // handle the error
    console.error(error);
  }
);
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In the code above, we import the forkJoin function from the RxJS library. We then create two separate observables that we want to combine using forkJoin.

We pass the array of observables to the forkJoin function, and then subscribe to it.

When all the observables complete, the forkJoin function will pass an array of their results to the subscriber's next callback. In this case, we use array destructuring to assign each result to a separate variable.

If any of the observables fail, the forkJoin function will immediately call the subscriber's error callback, and we can handle the error there.