javascript - 管道内的映射被忽略并且不会触发http调用

Question

我在调用效果上的 Web 服务时遇到问题

我在这里创建了效果

$LoadSchedulingsByMission = createEffect(() =>
  this.actions$.pipe(
    ofType<any>(ESchedulesActions.GetSchedulesByDirection),
    mergeMap(action =>
      this.apiCallsService.getDirections(action.payload, '2016-04-18').pipe(
        map(trips => ({ type: ESchedulesActions.GetSchedulesByDirectionSuccess, payload: trips })),
        catchError(() => EMPTY)
      )
    )
  )
);

采用字符串数组的 GetSchedulesByDirection 操作

export class GetDirections implements Action {
  public readonly type = ESchedulesActions.GetSchedulesByDirection;
  constructor(public payload: string[]) {}
}

然后我调用一个 http 服务，该服务采用上面的字符串数组。

getDirections(dataArrayToLoop: string[], date:string) {
  const groupByDirection:any={};
  dataArrayToLoop.map(elm=> {
    let dirUrl=`.....date=${date}&directions=${elm}`
    this.http.get<ISchedules>(dirUrl).pipe(map(dirData=>{
      groupByDirection[elm].push(dirData.data)
    }))
  })
  return of(groupByDirection);
}

最后成功操作

export class GetDirectionsSuccess implements Action {
  public readonly type = ESchedulesActions.GetSchedulesByDirectionSuccess;
  constructor(public payload: ISchedules) {}
}

reducer

case ESchedulesActions.GetSchedulesByDirection: {
  return {
    ...state,
  };
}
case ESchedulesActions.GetSchedulesByDirectionSuccess: {
  return {
    ...state,
    directions: action.payload
  };
}

问题是没有触发http调用，我验证了dataarray不为空

Answer 1

您将在回调发生之前返回 of(groupByDirection)。你需要这样的东西:

getDirections(dataArrayToLoop: string[], date:string) {
  const groupByDirection = dataArrayToLoop.map(elm => {
    let dirUrl=`.....date=${date}&directions=${elm}`;

    return this.http.get<ISchedules>(dirUrl).pipe(
      map(dirData=> dirData.data),
    );
  })
  return combineLatest(groupByDirection);
}