Question

使用React和Redux制作简单的天气应用程序时遇到麻烦。

我有两个减速器。一种是将数据添加到数组中，另一种是使用find方法从数组中删除数据。

这是代码：

// actions

// fetching weather api 

export const fetchWeather = term => {
  return async dispatch => {
    const res = await api.get(
      `/data/2.5/weather?q=${term}&APPID=132123123132`
    );
    dispatch({ type: "FETCH_WEATHER", payload: res.data });
  };
};

// delete a list that matches the selected id

export const listDelete = id => {
  return {
    type: "LIST_DELETE",
    paylod: id
  };
};

// reducers 

// reducer that put a new data into an array

const reducerIndex = (state = [], action) => {
  switch (action.type) {
    case "FETCH_WEATHER":
      return [...state, action.payload];
    default:
      return state;
  }
};

// reducer that deleting the data that id selected 

const reducerIndexDel = (state = [], action) => {
  switch (action.type) {
    case "LIST_DELETE":
      return state.find(city => city.id !== action.payload);
    default:
      return state;
  }
};

export default combineReducers({
  reducerIndex,
  reducerIndexDel
});

您可能知道，浏览器给我一个错误，提示“给定操作“ LIST_DELETE”，减速器“ reducerIndexDel”返回未定义。”

我能够获取想要的数据，但是如何使reducerIndexDel能够识别以前的状态？

Answer 1

只需使用filter即可获取不包含具有ID的城市的州。

return state.filter(city => city.id !== action.payload)

Answer 2

我认为您在listDelete函数中对“有效载荷”的拼写错误。

您正在尝试访问action.payload，但实际上它被写为paylod。

如何在redux中获得以前的状态？

2 个答案: