Angular / NgRx: 处理表单依赖于NGRX动作
创始人
2024-10-15 05:00:36
0

在Angular项目中,可以使用NgRx来管理应用程序的状态。当处理表单时,可以使用NGRX动作来处理表单的依赖关系。下面是一个示例解决方法:

首先,安装必要的依赖项。在命令行中运行以下命令:

npm install @ngrx/store @ngrx/effects --save

然后,创建一个名为form.actions.ts的文件,并添加以下代码:

import { createAction, props } from '@ngrx/store';

export const loadForm = createAction('[Form] Load Form');
export const loadFormSuccess = createAction('[Form] Load Form Success', props<{ form: any }>());
export const loadFormFailure = createAction('[Form] Load Form Failure', props<{ error: any }>());
export const updateForm = createAction('[Form] Update Form', props<{ form: any }>());
export const submitForm = createAction('[Form] Submit Form', props<{ form: any }>());
export const submitFormSuccess = createAction('[Form] Submit Form Success');
export const submitFormFailure = createAction('[Form] Submit Form Failure', props<{ error: any }>());

然后,创建一个名为form.reducer.ts的文件,并添加以下代码:

import { createReducer, on } from '@ngrx/store';
import * as FormActions from './form.actions';

export interface FormState {
  form: any;
  loading: boolean;
  error: any;
}

export const initialState: FormState = {
  form: null,
  loading: false,
  error: null
};

export const formReducer = createReducer(
  initialState,
  on(FormActions.loadForm, state => ({
    ...state,
    loading: true,
    error: null
  })),
  on(FormActions.loadFormSuccess, (state, { form }) => ({
    ...state,
    form,
    loading: false
  })),
  on(FormActions.loadFormFailure, (state, { error }) => ({
    ...state,
    error,
    loading: false
  })),
  on(FormActions.updateForm, (state, { form }) => ({
    ...state,
    form
  })),
  on(FormActions.submitForm, state => ({
    ...state,
    loading: true,
    error: null
  })),
  on(FormActions.submitFormSuccess, state => ({
    ...state,
    loading: false
  })),
  on(FormActions.submitFormFailure, (state, { error }) => ({
    ...state,
    error,
    loading: false
  }))
);

接下来,创建一个名为form.effects.ts的文件,并添加以下代码:

import { Injectable } from '@angular/core';
import { Actions, createEffect, ofType } from '@ngrx/effects';
import { of } from 'rxjs';
import { catchError, map, mergeMap } from 'rxjs/operators';
import * as FormActions from './form.actions';
import { FormService } from './form.service';

@Injectable()
export class FormEffects {
  loadForm$ = createEffect(() =>
    this.actions$.pipe(
      ofType(FormActions.loadForm),
      mergeMap(() =>
        this.formService.getForm().pipe(
          map(form => FormActions.loadFormSuccess({ form })),
          catchError(error => of(FormActions.loadFormFailure({ error })))
        )
      )
    )
  );

  submitForm$ = createEffect(() =>
    this.actions$.pipe(
      ofType(FormActions.submitForm),
      mergeMap(({ form }) =>
        this.formService.submitForm(form).pipe(
          map(() => FormActions.submitFormSuccess()),
          catchError(error => of(FormActions.submitFormFailure({ error })))
        )
      )
    )
  );

  constructor(
    private actions$: Actions,
    private formService: FormService
  ) {}
}

然后,创建一个名为form.service.ts的文件,并添加以下代码:

import { Injectable } from '@angular/core';
import { HttpClient } from '@angular/common/http';
import { Observable } from 'rxjs';

@Injectable({
  providedIn: 'root'
})
export class FormService {
  constructor(private http: HttpClient) {}

  getForm(): Observable {
    return this.http.get('api/form');
  }

  submitForm(form: any): Observable {
    return this.http.post('api/submit', form);
  }
}

最后,在需要使用表单的组件中,添加以下代码:

import { Component, OnInit } from '@angular/core';
import { Store } from '@ngrx/store';
import { Observable } from 'rxjs';
import * as FormActions from './form.actions';
import { FormState } from './form.reducer';

@Component({
  selector: 'app

相关内容

热门资讯

Android Recycle... 要在Android RecyclerView中实现滑动卡片效果,可以按照以下步骤进行操作:首先,在项...
安装apache-beam==... 出现此错误可能是因为用户的Python版本太低,而apache-beam==2.34.0需要更高的P...
Android - 无法确定任... 这个错误通常发生在Android项目中,表示编译Debug版本的Java代码时出现了依赖关系问题。下...
Android - NDK 预... 在Android NDK的构建过程中,LOCAL_SRC_FILES只能包含一个项目。如果需要在ND...
Akka生成Actor问题 在Akka框架中,可以使用ActorSystem对象生成Actor。但是,当我们在Actor类中尝试...
Agora-RTC-React... 出现这个错误原因是因为在 React 组件中使用,import AgoraRTC from “ago...
Alertmanager在pr... 首先,在Prometheus配置文件中,确保Alertmanager URL已正确配置。例如:ale...
Aksnginxdomainb... 在AKS集群中,可以使用Nginx代理服务器实现根据域名进行路由。以下是具体步骤:部署Nginx i...
AddSingleton在.N... 在C#中创建Singleton对象通常是通过私有构造函数和静态属性来实现,例如:public cla...
Alertmanager中的基... Alertmanager中可以使用repeat_interval选项指定在一个告警重复发送前必须等待...