Question

我的NgRx效果有问题。

应用程序正确地添加到商店中，不幸的是，我没有执行请求的效果，即，在启动添加新车时，将其添加到商店中就这样了。问题是我的效果没有控制台日志，没有url错误导致的http错误，一无所有。

我的应用代码：

减速器

import { Action } from '@ngrx/store';
import * as CarActions from './car.actions';
import { Car } from 'src/models/car.model';

const initialState: Car = {
   brand: '',
   model: ''
};

export function carReducer(state: Car[] = [initialState], action: CarActions.Actions) {

    switch (action.type) {
        case CarActions.ADD_CAR:
            return [...state, action.payload];
        case CarActions.ADD_CAR_FAIL:
            return {
                ...state,
                carError: action.payload,
            };
        default:
            return state;
    }
}

状态

import { Car } from './../../models/car.model';

export interface AppState {
  readonly car: Car;
}

动作

import { Action } from '@ngrx/store';
import { Car } from './../../models/car.model';

export const ADD_CAR       = '[CAR] Add';
export const ADD_CAR_FAIL    = '[CAR] Fail';

export class AddCar implements Action {
    readonly type = ADD_CAR;

    constructor(public payload: Car) {}
}

export class AddCarFail implements Action {
    readonly type = ADD_CAR_FAIL;

    constructor(public payload: string) {}
}

export type Actions = AddCar | AddCarFail;

效果

import { Actions, Effect, ofType } from '@ngrx/effects';
import * as CarActions from './car.actions';
import { HttpClient } from '@angular/common/http';
import { Injectable } from '@angular/core';
import { switchMap, catchError, map, tap } from 'rxjs/operators';
import { of } from 'rxjs';

@Injectable()
export class CarEffects {
    @Effect()
    carAdd = this.actions$.pipe(
        ofType(CarActions.ADD_CAR),
        switchMap((carData: CarActions.AddCar) => {
            console.log('true');
            return this.http.post('http://myapi.com/api', { brand: carData.payload.brand, model: carData.payload.model }).pipe(map(resData => {
                localStorage.setItem('test', 'asdasdasd');
            }),
                catchError(errorRes => {
                    console.log(errorRes);
                    const errorMessage = 'An unknown error occurred!';
                    if (!errorRes.error || !errorRes.error.error) {
                        return of(new CarActions.AddCarFail(errorMessage));
                    }

                    console.log(errorRes.error.error.message);
                    return of(new CarActions.AddCarFail(errorRes.error.error.message));
                }));
        })
    );

    constructor(
        private actions$: Actions,
        private http: HttpClient) { }
}

App.Module.ts

import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';

import { AppComponent } from './app.component';
import { CarComponent } from './car/car.component';
import { StoreModule } from '@ngrx/store';
import { carReducer } from './car/car.reducer';
import { HttpClientModule } from '@angular/common/http';
import { StoreDevtoolsModule } from '@ngrx/store-devtools';


@NgModule({
  declarations: [
    AppComponent,
    CarComponent
  ],
  imports: [
    BrowserModule,
    StoreModule.forRoot({ car: carReducer }),
    HttpClientModule,
    StoreDevtoolsModule.instrument({
      maxAge: 5
    })
  ],
  providers: [],
  bootstrap: [AppComponent]
})
export class AppModule { }

最重要的是，我的代码是否很好地使用了NgRx？

Answer 1

您没有在模块中添加效果

import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';

import { AppComponent } from './app.component';
import { CarComponent } from './car/car.component';
import { StoreModule } from '@ngrx/store';
import { carReducer } from './car/car.reducer';
import { HttpClientModule } from '@angular/common/http';
import { StoreDevtoolsModule } from '@ngrx/store-devtools';
import { EffectsModule } from '@ngrx/effects';
import { CarEffects } from './car/car.effects';


@NgModule({
  declarations: [
    AppComponent,
    CarComponent
  ],
  imports: [
    BrowserModule,
    StoreModule.forRoot({ car: carReducer }),
    HttpClientModule,
    EffectsModule.forRoot([CarEffects]),
    StoreDevtoolsModule.instrument({
      maxAge: 5
    })
  ],
  providers: [],
  bootstrap: [AppComponent]
})
export class AppModule { }

Answer 2

您需要导入EffectsModule才能注册效果。

在app.module.ts中，您可以执行以下操作：

import {CarEffects} from 'path/to/careffects';

@NgModule({
  declarations: [
    AppComponent,
    CarComponent
  ],
  imports: [
    BrowserModule,
    StoreModule.forRoot({ car: carReducer }),
    HttpClientModule,
    StoreDevtoolsModule.instrument({
      maxAge: 5
    }),
    //                               ADD THIS BELOW !!
    EffectsModule.forRoot(
      [CarEffects]
    )
  ],
  providers: [],
  bootstrap: [AppComponent]
})

我的NgRx效果不起作用，什么也没发生

2 个答案: