使用不可变的JS和Redux - action是未定义的。

Question

我正在使用Redux和Immutable JS。我把商店设成这样

import { combineReducers } from 'redux-immutable';

...
const rootReducer = combineReducers({});    
import { initialState } from '../reducers/...';

export const store = createStore(
    combineReducers(rootReducer, initialState),
    composeEnhancers(
        applyMiddleware(...middleware)
    )
);

现在我得到以下错误

// reducers/.../initialState.js

export function foo(state = initialState, action) {
    switch (action.type) {
     ...
...

TypeError:无法读取未定义的属性“类型”

它突出了switch (action.type) {。

当我不使用redux-immutable并像这样设置我的商店时

import { ..., combineReducers } from 'redux';    

export const store = createStore(
    combineReducers({ initialState }),
    composeEnhancers(
        applyMiddleware(...middleware)
    )
);

我没有搞错。我不明白为什么它说action.type是undefined。有什么想法吗？

Answer 1

combineReducers只使用减速器：

const yourRootReducer = combineReducers({ someReducer, someOtherReducer })

It 不需要 initialState，您的个别商店可以( createStore，尽管您通常不需要在那里)。

您对createStore的调用应该是：

const store = createStore(
  rootReducer,
  initialState, // can be undefined
  composeEnhancers(
    applyMiddleware(...middleware)
  )
);

假设中间件是一个数组。

Answer 2

我认为你的代码应该是这样的

export const store = createStore(
    rootReducer, initialState,
    composeEnhancers(
        applyMiddleware(...middleware)
    )
);
// I removed the combineReducers()

参考资料：https://github.com/gajus/redux-immutable#usage

示例：

import {
  combineReducers
} from 'redux-immutable';

import {
  createStore
} from 'redux';

const initialState = Immutable.Map();
const rootReducer = combineReducers({});  // we use the combineReducers() here
const store = createStore(rootReducer, initialState); // and don't need to use it here

Answer 3

您的initialState不应该是减速机。你应该把所有的减速机都组合起来。

您的初始状态应该是object (状态)。

(例如)

{
 loaded: true,
 someDataString: ''
}