如何访问Redux减速机内部的状态？

Question

我有一个reducer,为了计算新的状态,我需要来自动作的数据,以及来自该reducer未管理的部分状态的数据.具体来说,在减速机中我将在下面显示,我需要访问该accountDetails.stateOfResidenceId字段.

initialState.js:

export default {
    accountDetails: {
        stateOfResidenceId: '',
        accountType: '',
        accountNumber: '',
        product: ''
    },
    forms: {
        blueprints: [

        ]
    }
};

formsReducer.js:

import * as types from '../constants/actionTypes';
import objectAssign from 'object-assign';
import initialState from './initialState';
import formsHelper from '../utils/FormsHelper';
export default function formsReducer(state = initialState.forms, action) {
  switch (action.type) {
    case types.UPDATE_PRODUCT: {
        //I NEED accountDetails.stateOfResidenceId HERE
        console.log(state);
        const formBlueprints = formsHelper.getFormsByProductId(action.product.id);
        return objectAssign({}, state, {blueprints: formBlueprints});
    }

    default:
      return state;
  }
}

index.js(root reducer):

import { combineReducers } from 'redux';
import accountDetails from './accountDetailsReducer';
import forms from './formsReducer';

const rootReducer = combineReducers({
    accountDetails,
    forms
});

export default rootReducer;

我该如何访问此字段？

Answer 1

我会使用thunk,这是一个例子:

export function updateProduct(product) {
  return (dispatch, getState) => {
    const { accountDetails } = getState();

    dispatch({
      type: UPDATE_PRODUCT,
      stateOfResidenceId: accountDetails.stateOfResidenceId,
      product,
    });
  };
}

基本上,您可以获得操作所需的所有数据,然后您可以将该数据发送到reducer.

Answer 2

您可以选择编写更多逻辑,而不仅仅是使用combineReducers,或者在操作中包含更多数据.Redux FAQ涵盖了这个主题:http://redux.js.org/docs/faq/Reducers.html#reducers-share-state.

此外,我目前正在为Redux文档开发一组关于"构建减速器"主题的新页面,您可能会发现这些页面很有帮助.目前WIP的页面在https://github.com/markerikson/redux/blob/structuring-reducers-page/docs/recipes/StructuringReducers.md.