Question

我已经研究了一些实现Redux（NgRx）的Angular应用程序。我不知道我当前项目的问题。

动作：

export class GetUserFromStorage implements Action {
  readonly type = UserActionTypes.GetUserFromStorage;
}

export class GetUserFromStorageSuccess implements Action {
  readonly type = UserActionTypes.GetUserFromStorageSuccess;
  constructor(public payload: User | null) { }
}

export class GetUserFromStorageFail implements Action {
  readonly type = UserActionTypes.GetUserFromStorageFail;
  constructor(public payload: string) { }
}

减速器：

case UserActionTypes.GetUserFromStorageSuccess:
    return {
        ...state,
        user: action.payload,
        error: ''
    };

case UserActionTypes.GetUserFromStorageFail:
    return {
        ...state,
        error: action.payload
    };

效果：

@Effect() getUserFromStorage$:
Observable<userActions.GetUserFromStorageSuccess | userActions.GetUserFromStorageFail>
    = this.actions$.pipe(
        ofType(userActions.UserActionTypes.GetUserFromStorage),
        tap(() => console.log('GETUserToStorage$', )),
        mergeMap((action: userActions.GetUserFromStorage) =>
            this.storageService.getItem(StorageKeys.USER).pipe(
                map((user: User | null) =>
                    new userActions.GetUserFromStorageSuccess(user)),
                catchError((error: string) =>
                    of(new userActions.GetUserFromStorageFail(error)))
                ))
            );

在auth.service.ts中，我订阅了商店，并调度了一些操作。

this.store.dispatch(new userActions.GetUserFromStorage());

this.store.pipe(select(userReducer.getUser)).subscribe(
    (user: User) => {
        console.log('user TEST: ', user);
        this.user = user;
    }
);

我已经安装了ReduxDevTools。将触发GetUserFromStorage操作，但不会触发getUserFromStorage $效果。 console.logged的'user TEST'值表明'user'为'null'。有什么想法吗？谢谢。

Answer 1

确保您实际上已经“激活”了它们。

可注射的效果：

@Injectable()

export class FooEffects {

  @Effect() getUserFromStorage$:
Observable<userActions.GetUserFromStorageSuccess | userActions.GetUserFromStorageFail>
    = this.actions$.pipe(
        ofType(userActions.UserActionTypes.GetUserFromStorage),
        tap(() => console.log('GETUserToStorage$', )),
        mergeMap((action: userActions.GetUserFromStorage) =>
            this.storageService.getItem(StorageKeys.USER).pipe(
                map((user: User | null) =>
                    new userActions.GetUserFromStorageSuccess(user)),
                catchError((error: string) =>
                    of(new userActions.GetUserFromStorageFail(error)))
                ))
            );
}

app.module.ts：

import {EffectsModule} from '@ngrx/effects';

imports: [
  EffectsModule.forRoot([
    FooEffects
  ])
]

角度：ngrx效果不触发

1 个答案: