I have a service that has a method foo. Inside the method I subscribe to an observable (http-client).
foo () : boolean
{
let ret : false;
this.http.get ("/blabla").subscribe (
(resp) =>
{
ret = true;
}
return ret;
);
I like to return a boolean value from foo that depends on the get. That is not working because http.get is asynchrouns - return is called before http.get finished.
How can I make this synchronous?
EDIT
Returning the observable instead boolean is not an option here. That is because I handle the response of get in foo (not shown here) but I also need to act out of foo depending of its return.
EDIT2
I extended my sample with pipe and tap. Now I return the http.get-observable for outside the service and I process the http.get-result with tap.
foo () : Observable <any>
{
return this.http.get ("/blabla").pipe (tap (x => handlehere ()));
}
As far I see there is only one uglyness with it. I have the complexity of parsing the get-result inside AND outside of foo. I would prefer a simple boolean outside of foo.
This method can only run asynchronously so you don't have a lot of option. Returning the obsersable and subscribe or return a promise. Perhaps returning a Promise will suite more your need in term of comprehention.
In your service : the foo method :
async foo() {
const result = await this.http.get("/blabla").toPromise();
// do what you want with result
return result;
}
How to call it :
this.myService.foo().then( (result) => {
// Do what you want with the result
});
Collected from the Internet
Please contact [email protected] to delete if infringement.
Comments