javascript - How to write a function with an Observable? -

i want create function returns observable.the description of function follows:

the function should delayedalert(message:string, time:number) returns observable.
the function should contain settimeout function inside delayedalert prints message after set 'time' value.

ex:

delayedalert(message, time){ return new observable//how implement settimeout function here?

use observable.create create observable, , in first callback, write logic populate observable, in case settimeout.

function delayedalert(msg, time) {   return observable.create(     observer => settimeout(() => observer.onnext(msg), time)); }

then use it:

delayedalert("hi, sally", 1000).subscribe(msg => alert(msg));

however, if using observables, don't need use settimeout; use delay instead, applied of, creates observable individual value(s):

function delayedalert(msg, time) {   return observable.of(msg).delay(time); }

since it's easy write way, don't need delayedalert function @ all:

const observable = observable.of("hi, sally").delay(1000);  observable.subscribe(msg => alert(msg));

Insert