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

To use the zipAll function from the rxjs library in JavaScript, you first need to import it from the rxjs package.

index.tsx
import { of } from 'rxjs';
import { map, zipAll } from 'rxjs/operators';
73 chars
3 lines

Here, we are importing the of function, which is used to create an observable from static values, and the map and zipAll functions, which are used to transform and combine observables, respectively.

Next, you can create two or more observables to combine using the zipAll function. For example, let's create two observables that emit a sequence of numbers at different intervals:

index.tsx
const obs1 = of(1, 2, 3);
const obs2 = of(4, 5, 6).pipe(map(val => val * 2));
78 chars
3 lines

Here, obs1 will emit the numbers 1, 2, and 3 immediately, while obs2 will emit the numbers 4, 10, and 12 after multiplying each value emitted by 2.

Finally, you can use the zipAll function to combine these two observables into a single observable that emits an array of values, where each value corresponds to the value emitted by each observable:

index.tsx
obs1.pipe(zipAll(obs2)).subscribe(val => console.log(val));
60 chars
2 lines

Here, we pass obs2 to the zipAll function as an argument, which combines it with obs1. The resulting observable emits an array for each value, where the first element corresponds to the value emitted by obs1 and the second element corresponds to the value emitted by obs2. The subscribe method is then used to log each array to the console.

Output:

index.tsx
[1, 4]
[2, 10]
[3, 12]
23 chars
4 lines

In summary, the zipAll function in rxjs is a powerful tool that allows you to combine multiple observables into a single observable, where each value emitted corresponds to the values emitted by each observable.