Establecer el valor seleccionado del desplegable usando FormControl en Angular
this.countryForm.controls['country'].valueChanges.subscribe(country =>
this.person.country = country;
);
// initialize by finding the correct country object (this will overwrite the person's country object)
this.countryForm.controls['country'].setValue(countries.filter(c => c.id === person.country.id));
Karan Najwani