What Is a Switchmap

The switchMap operator maps each value to an observable, then it flattens all of the inner observables. It basically projects each source value to an observable which is then merged in the output observable, emitting values only from the most recently projected observable.

What is a switchMap in Angular?

The Angular SwitchMap maps each value from the source observable into an inner observable, subscribes to it, and then starts emitting the values from it. It creates a new inner observable for every value it receives from the Source. … Basically it switches to the newest observable discarding all other.

What is the difference between mergeMap and switchMap?

So here’s the simple difference — switchMap cancels previous HTTP requests that are still in progress, while mergeMap lets all of them finish.