Angular http.post without .subscribe callback

Question

I'm wondering if I can make just a http post request without subscribing on callbacks, something like this

 this._http.post('/list/items/update?itemId=' + itemId + "&done=" + done, null);

instead of this

 this._http.post('/list/items/update?itemId=' + itemId + "&done=" + done, null)
        .subscribe();

Answer 1

I do not think you can.

http.post (and get, put, delete, etc) returns a cold Observable, i.e. an Observable for which:

its underlying producer is created and activated during subscription

Source.

This means the function represented by the Observable is activated only with the subscribe() method.