使用Redux Toolkit的方法:

export const createRootReducer = (history: History) => {
  const rootReducerFn = combineReducers({
    auth: authReducer,
    users: usersReducer,
    ...allOtherReducers,
    router: connectRouter(history),
  });

  return (state: Parameters<typeof rootReducerFn>[0], action: Parameters<typeof rootReducerFn>[1]) =>
    rootReducerFn(action.type === appActions.reset.type ? undefined : state, action);
};

只是对@dan-abramov答案的扩展，有时我们可能需要保留某些被重置的键。

const retainKeys = ['appConfig'];

const rootReducer = (state, action) => {
  if (action.type === 'LOGOUT_USER_SUCCESS' && state) {
    state = !isEmpty(retainKeys) ? pick(state, retainKeys) : undefined;
  }

  return appReducer(state, action);
};

NGRX4更新

如果您正在迁移到NGRX 4，您可能已经从迁移指南中注意到用于组合reducer的rootreducer方法已经被ActionReducerMap方法所取代。起初，这种新的做事方式可能会使重置状态成为一个挑战。它实际上很简单，但这样做的方式已经改变了。

这个解决方案的灵感来自NGRX4 Github文档的元还原器API部分。

首先，让我们假设你正在使用NGRX的新ActionReducerMap选项像这样组合你的reducer:

//index.reducer.ts
export const reducers: ActionReducerMap<State> = {
    auth: fromAuth.reducer,
    layout: fromLayout.reducer,
    users: fromUsers.reducer,
    networks: fromNetworks.reducer,
    routingDisplay: fromRoutingDisplay.reducer,
    routing: fromRouting.reducer,
    routes: fromRoutes.reducer,
    routesFilter: fromRoutesFilter.reducer,
    params: fromParams.reducer
}

现在，假设你想从app。module内部重置状态

//app.module.ts
import { IndexReducer } from './index.reducer';
import { StoreModule, ActionReducer, MetaReducer } from '@ngrx/store';
...
export function debug(reducer: ActionReducer<any>): ActionReducer<any> {
    return function(state, action) {

      switch (action.type) {
          case fromAuth.LOGOUT:
            console.log("logout action");
            state = undefined;
      }
  
      return reducer(state, action);
    }
  }

  export const metaReducers: MetaReducer<any>[] = [debug];

  @NgModule({
    imports: [
        ...
        StoreModule.forRoot(reducers, { metaReducers}),
        ...
    ]
})

export class AppModule { }

这基本上是用NGRX 4达到同样效果的一种方法。

只需编辑声明约简的文件

import { combineReducers } from 'redux';

import gets from '../';

const rootReducer = (state, action) => {
  let asReset = action.type === 'RESET_STORE';

  const reducers = combineReducers({
    gets,
  });

  const transition = {
    true() {
      return reducers({}, action);
    },
    false() {
      return reducers(state, action);
    },
  };
  return transition[asReset] && transition[asReset]();
};

export default rootReducer;

为了避免Redux引用初始状态的相同变量，我的建议是:

// write the default state as a function
const defaultOptionsState = () => ({
  option1: '',
  option2: 42,
});

const initialState = {
  options: defaultOptionsState() // invoke it in your initial state
};

export default (state = initialState, action) => {

  switch (action.type) {

    case RESET_OPTIONS:
    return {
      ...state,
      options: defaultOptionsState() // invoke the default function to reset this part of the state
    };

    default:
    return state;
  }
};

我已经创建了清除状态的操作。因此，当我分派登出动作创建者时，我也分派动作来清除状态。

用户记录动作

export const clearUserRecord = () => ({
  type: CLEAR_USER_RECORD
});

注销操作创建器

export const logoutUser = () => {
  return dispatch => {
    dispatch(requestLogout())
    dispatch(receiveLogout())
    localStorage.removeItem('auth_token')
    dispatch({ type: 'CLEAR_USER_RECORD' })
  }
};

减速机

const userRecords = (state = {isFetching: false,
  userRecord: [], message: ''}, action) => {
  switch (action.type) {
    case REQUEST_USER_RECORD:
    return { ...state,
      isFetching: true}
    case RECEIVE_USER_RECORD:
    return { ...state,
      isFetching: false,
      userRecord: action.user_record}
    case USER_RECORD_ERROR:
    return { ...state,
      isFetching: false,
      message: action.message}
    case CLEAR_USER_RECORD:
    return {...state,
      isFetching: false,
      message: '',
      userRecord: []}
    default:
      return state
  }
};

我不确定这是否是最佳的?