Angular 2: Convert Observable to Promise

Question

Q) How do I convert the following observable to a promise so I can call it with .then(...)?

My method I want to convert to a promise:

  this._APIService.getAssetTypes().subscribe(     assettypes => {         this._LocalStorageService.setAssetTypes(assettypes);     },     err => {         this._LogService.error(JSON.stringify(err))     },     () => {}   );  

The service method it calls:

  getAssetTypes() {     var method = "assettype";     var url = this.apiBaseUrl + method;      return this._http.get(url, {})       .map(res => <AssetType[]>res.json())       .map((assettypes) => {         assettypes.forEach((assettypes) => {           // do anything here you might need....       });       return assettypes;     });         }   

Thanks!

Answer 1

rxjs7

lastValueFrom(of('foo')); 

https://indepth.dev/posts/1287/rxjs-heads-up-topromise-is-being-deprecated

rxjs6

https://github.com/ReactiveX/rxjs/issues/2868#issuecomment-360633707

Don't pipe. It's on the Observable object by default.

Observable.of('foo').toPromise(); // this 

rxjs5

import 'rxjs/add/operator/toPromise'; import 'rxjs/add/operator/map';  ...  this._APIService.getAssetTypes() .map(assettypes => {   this._LocalStorageService.setAssetTypes(assettypes); }) .toPromise() .catch(err => {   this._LogService.error(JSON.stringify(err)); });