要么将根组件包装在 <Provider> 中，要么将“store”作为道具显式传递给“Connect(CharacterList)

Question

我正在尝试测试我的 React “supersquadapp”并收到以下错误。

未捕获的错误：在“Connect(CharacterList)”的上下文或道具中找不到“存储”。要么将根组件包装在 a 中，要么将“store”作为道具显式传递给“Connect(CharacterList)”。

characterlist.js

import React, { Component } from 'react';
import { connect } from 'react-redux';

class CharacterList extends Component {
    render() {
        console.log('this.props', this.props);
        return (
            <div>
                <h4>characters</h4>
            </div>
        )
    }

}
function mapStateToProps(state) {
    return {
        characters: state.characters
    }
}

export default connect(mapStateToProps, null)(CharacterList);

app.js

import React, {Component} from 'react';
import CharacterList from './CharacterList';

class App extends Component {
    render() {
        return (
            <div>
                <h2>SUPER SQUAD</h2>
                <CharacterList />
            </div>
        )
    }
} 
export default App;

index.js

import React from 'react';
import ReactDOM from 'react-dom';
import App from './Components/App';

import { createStore } from 'redux';
import { Provider } from 'react-redux';

import rootReducers from './reducers';
import { addCharacterById } from './actions';


const store = createStore(rootReducers);
console.log(store.getState());
store.subscribe(() => console.log('store',store.getState()))
store.dispatch(addCharacterById(3));

ReactDOM.render(
    <Provider>
        <App />
     </Provider>
    ,document.getElementById('root')
)

character.js（在 reducers 文件夹中）

import characters_json from '../Data/characters.json';
import { ADD_CHARACTER } from '../actions';

function characters(state = characters_json, action) {
    switch(action.type) {
        case ADD_CHARACTER:
        let characters = state.filter(item => item.id !== action.id);
        return characters;
        default:
            return state;
    }
}
export default characters;

heroes.js(reducers 文件夹)

import { ADD_CHARACTER } from '../actions';
import {createCharacter} from './helper';

function heroes(state = [], action) {
    switch(action.type) {
        case ADD_CHARACTER:
        let heroes = [...state, createCharacter(action.id)];
        return heroes;
        default:
        return state;
    }
}
export default heroes;

helper.js(reducers 文件夹)

import characters_json from '../Data/characters.json';

export function createCharacter(id) {
    let character = characters_json.find(c => c.id === id);
    return character;
}

index.js(reducers 文件夹)

import { combineReducers } from 'redux';
import characters from './characters_reducer';
import heroes from './heroes_reducer';


const rootReducer = combineReducers({
    characters,
    heroes
})
export default rootReducer;

index.js（动作文件夹）

export const ADD_CHARACTER = 'ADD_CHARACTER';

export function addCharacterById(id) {
    const action = {
        type:ADD_CHARACTER,
        id
    }
    return action;
}

组件出现上述错误：

在 Connect(CharacterList) 中（在 App.js:9 处）

在 div 中（在 App.js:7 处）

在应用程序中（在 index.js:19）

在提供者中（在 index.js:18）

请帮帮我...？

Answer 1

如果您正在运行测试并且您有类似 alechill 的答案，则需要在测试中更改此内容，例如：

let mockedStore = configureStore([])({});
test('some test', () => {
  const wrapper = mount(<SomeComponent foo="bar" />, {
    context: { store: mockedStore },
    childContextTypes: { store: PropTypes.object.isRequired }
  });
  expect(.... your tests here);
});

Answer 2

您必须将 store 实例传递给 Provider...

ReactDOM.render(
    <Provider store={store}>
        <App />
     </Provider>
    , document.getElementById('root')
)