Call function in function in other function in angular2 typeScript

You need to bind the passed function to this so that the scope is saved:

constructor(private heroService :HeroService) {} 

getHeroes() {
    this.heroService.getHeroes().then(response => this.heroes = response);
}

addHero(hero :Hero) {
    this.heroService.create(hero).then(function(response) {
        this.getHeroes();
    }.bind(this));
}

Or use an arrow function which saves the scope of this:

addHero(hero :Hero) {
    this.heroService.create(hero).then(response => {
        this.getHeroes();
    });
}

But getHeroes is async, so if you want to wait for it you'll need to do:

constructor(private heroService :HeroService) {} 

getHeroes() {
    return this.heroService.getHeroes().then(response => this.heroes = response);
}

addHero(hero :Hero) {
    this.heroService.create(hero).then(response => {
        this.getHeroes().then(() => {
            // do what ever
        };
    });
}