REDUX: Error: Actions may not have an undefined "type" property. Have you misspelled a constant?

Question

我正在学习 Redux，我对这里发生的事情感到很困惑。我正在使用 thunk 并且 GET_ITEMS 在我的减速器中所以我不确定我做错了什么？错误在 dispatch(getItemsAction());

Redux.js

function reducer(state, action) {
    switch (action.type) {
        case 'GET_ITEMS':
            return {
                ...state,
                items: action.payload,
                loading: false,
            };
        case 'ADD_ITEM':
            return {
                ...state,
                items: [...state.items, action.payload],
            };
        case 'DELETE_ITEM':
            return {
                ...state,
                items: state.items.filter(item => item.id !== action.payload),
            };
        case 'ITEMS_LOADING':
            return {
                ...this.state,
                loading: true,
            };
        default:
            return state;
    }
}

export const getItemsAction = () => ({
    return(dispatch) {
        axios.get('api/items').then(response => {
            console.log(response);
            dispatch({ type: 'GET_ITEMS', payload: response.data });
        });
    },
});

ShoppingList.js

import { addItemAction, deleteItemAction, getItemsAction } from '../redux';

export default function ShoppingList() {
    const items = useSelector(state => state.items);

    const dispatch = useDispatch();
    const addItem = name => dispatch(addItemAction(name));
    const deleteItem = id => dispatch(deleteItemAction(id));

    useEffect(() => {
        dispatch(getItemsAction());
    }, []);

Answer 1

在顶部代码中，您 return以错误的方式进行了调度但实际上你需要像 cb 这样调用 dispatch 例如在 javascript 我们做这样的事情

const myfunc = () => cb => {
    cb('OK')
};

它在 javascript 中的回调，你必须 return 分派类似回调才能正常工作

export const getItemsAction = () => dispatch => {
    axios.get('api/items').then(response => {
            dispatch({
                type: 'GET_ITEMS',
                payload: response.data
            })
    });
};

最后别忘了用response.data

获取axios响应数据

Answer 2

该操作的正确语法是

export const getItemsAction = () => dispatch => {
    axios.get('/api/items').then(res =>
        dispatch({
            type: 'GET_ITEMS',
            payload: res.data,
        })
    );
};

REDUX: Error: Actions may not have an undefined "type" property. Have you misspelled a constant?

REDUX: Error: Actions may not have an undefined "type" property. Have you misspelled a constant?

javascript

reactjs

redux

redux-thunk

react-hooks