带有 axios 返回多个值的 Redux Thunk 操作

Posted 2023-02-22

【中文标题】带有 axios 返回多个值的 Redux Thunk 操作

【英文标题】：Redux Thunk action with axios returning multiple values

【发布时间】：2020-06-13 22:33:01

【问题描述】：

我有一个 React 应用程序，它使用 redux-thunk 和 axios 来获取 API。该动作成功触发，但返回多个有效负载，这意味着它会触发多次。

我怎样才能让它只触发一次？

代码

动作

import Axios from "axios";
import  fetchEnglishLeagueTable  from "./ActionTypes";

export function fetchEnglishTable() 
  var url = "https://api.football-data.org/v2/competitions/PL/matches";
  var token = "52c8d88969d84ac9b17edb956eea33af";
  var obj = 
    headers:  "X-Auth-Token": token 
  ;
  return dispatch => 
    return Axios.get(url, obj)
      .then(res => 
        dispatch(
          type: fetchEnglishLeagueTable,
          payload: res.data
        );
      )
      .catch(e => 
        console.log("Cant fetch ", e);
      );
  ;

减速器

import  fetchEnglishLeagueTable  from "../actions/ActionTypes";
const initialState = 
  EnglishTable: 
;

const rootReducer = (state = initialState, action) => 
  switch (action.type) 
    case fetchEnglishLeagueTable:
      return 
        ...state,
        EnglishTable: action.payload
      ;
    default:
      return state;
  
;

export default rootReducer;

页面

const League = props => 
  useEffect(() => 
    props.getLeagueTable();
  , [props.leagueTable]);
  console.log(props.leagueTable);
  return <p>ihi</p>;
;
const mapStateToProps = state => (
  leagueTable: state.EnglishTable
);
const mapDispatchToProps = dispatch => 
  return  getLeagueTable: () => dispatch(fetchEnglishTable()) ;
;

export default connect(mapStateToProps, mapDispatchToProps)(League);

商店

import rootReducer from "./Reducer";
import thunk from "redux-thunk";

const store = createStore(rootReducer, applyMiddleware(thunk));

export default store;

这是它返回的

【参考方案1】：

只需从useEffect 的依赖数组中删除leagueTable，这样它只会在组件安装后获取它们。因为现在你有一个循环：

获取联赛 -> 联赛表更新 -> useEffect 发现 leagueTable 在依赖数组中发生了变化，并再次调用获取联赛，我们有一个循环。

const League = props => 
  useEffect(() => 
    props.getLeagueTable();
  , []); // <~ no props.leagueTable here
  console.log(props.leagueTable);
  return <p>ihi</p>;
;

希望对你有帮助:)