Unsubscribe from an Observable in Angular

Question

One of the best practices in Angular is to unsubscribe from Observables when we no longer need them. For that, do we have to do

Accepted Answer

```jsx
@Component({ ... })
export class AppComponent implements OnDestroy{
  this.subscription: Subscription<any>;

constructor(private userService: UserService){
     this.subscription = userService.getMessages().subscribe(messages => ...);
  }

ngOnDestroy(){
     this.subscription.unsubscribe()
  }
}
```

Answer

```jsx
@Component({ ... })
export class AppComponent {
  constructor(private userService: UserService){
     userService.getMessages(). subscribe(messages => ...).unsubscribe();
  }
}
```

Answer

```jsx
@Component({ ... })
export class AppComponent{
  constructor(private userService: UserService){
     const subscription = userService.getMessages().subscribe(messages => ...);
     subscription.close()
  }
}
```

Answer

```jsx
@Component({ ... })
export class AppComponent implements OnDestroy{
  this.subscription: Observable<any>;

constructor(private userService: UserService){
     this.subscription= userService.getMessages()
         this.subscription.subscribe(messages => ...);
  }

ngOnDestroy(){
     this.subscription.unsubscribe()
  }
}
```

Question from the Angular test

Unsubscribe from an Observable in Angular