canDeactivateGuard-ng5

canDeactivateGuard.ts

@Injectable()
export class CanDeactivateGuard implements CanDeactivate<UserFormComponent> {
  canDeactivate(component: UserFormComponent): boolean {
   
    if(component.hasUnsavedData()){
        if (confirm("You have unsaved changes! If you leave, your changes will be lost.")) {
            return true;
        } else {
            return false;
        }
    }
    return true;
  }
}