Question

我正在使用Angular 8和NGRX8。我有一个动作：

export const loadEnvironment = createAction(
  LicencingActionTypes.LoadEnvironment,
  props<{environment: Environment}>()
);

及相应的效果：

 loadEnvironment = createEffect(() => this.actions$.pipe(
    ofType(LicencingActionTypes.LoadEnvironment),
    exhaustMap((action) =>
      this.authService.
      getToken(LicencingEffects.getAuthDetailsForEnvironment(action.environment))
        .pipe(
          switchMap((token) => [
            AuthActions.onLogin({token: token}),
            LicencingActions.onLoadEnvironment({environment: action.environment})
          ]),
          catchError(error => of(AuthActions.onLoginError({error: error})))
        )
    )
  ));

我一直在阅读有关NGRX 8（https://ngrx.io/guide/effects#incorporating-state）的文档。

他们的示例表明，您可以仅使用action属性，而无需强制转换动作类型：

...
exhaustMap(action =>
        this.authService.login(action.credentials)
...

Webpack无法编译，并且出现以下错误：

ERROR in src/app/licencing/effects/licencing.effects.ts(20,69): error TS2339: Property 'environment' does not exist on type 'never'.

Screenshot of code with errors highlighted

我要去哪里错了？

Answer 1

尝试如下更改您的effect-

loadEnvironment = createEffect(() => this.actions$.pipe(
    ofType(loadEnvironment), //<-- this is your action
    exhaustMap(action => //<-- getting rid of extra parenthesis
      this.authService.
      getToken(LicencingEffects.getAuthDetailsForEnvironment(action.environment))
        .pipe(
          switchMap((token) => [
            AuthActions.onLogin({token: token}),
            LicencingActions.onLoadEnvironment({environment: action.environment})
          ]),
          catchError(error => of(AuthActions.onLoginError({error: error})))
        )
    )
  ));

参考样本implementation

Answer 2

动作必须在动作文件底部的类型联合中声明：

const all = union({
  info,
  appError
});

export type CoreActionsUnion = typeof all;

，然后在以该类型作为Actions的类型参数注入的Effects类构造函数中：

constructor(private actions$: Actions<CoreActionsUnion>) { }

Ngrx效果中的“从不”类型不存在属性

2 个答案: