Combine Observables in Angular like a pro

When working with observables in Angular, it’s important to know how to combine them to achieve the desired behavior. In this article, we will be exploring three methods for combining observables: merge(), concat(), and forkJoin(). These methods allow you to combine multiple observables into a single observable stream, making it easier to manage and handle the data.

Learn more about Observables in my other article: check it out!

merge()

The merge() method is used to combine multiple observables into a single observable stream that emits values from all the observables as they are emitted. This method is best used when you want to subscribe to multiple observables at the same time and handle the values as they come in.

const observable1 = of(1, 2, 3);
const observable2 = of(4, 5, 6);

const combined = merge(observable1, observable2);
combined.subscribe(val => console.log(val));
// Output: 1, 2, 3, 4, 5, 6

In this example, we are combining observable1 and observable2 using the merge() method. The combined observable will emit values from both observables as they are emitted. You can also pass in an optional argument to the merge() method which is the number of observables to emit from at once.