javascript - js文件类型错误: Dispatch is not a Function in actions.

Question

我正在使用 Redux-thunk 中间件开发 React-Redux 应用程序。当我尝试在 actions.js 文件中执行名为 removeStock() 的函数时，收到一条错误消息:“TypeError: Dispatch is not a function”:

action.js

export const deletePinnedStock = (user_id, stock_name, stock_id) => {
  return dispatch => {
    ApiService.delete("/users/" + user_id + "/stocks/" + stock_id)
    .then(response => {
      dispatch(removeStock(stock_name))
      console.log('here is the', response)
    }).catch((errors) => {
      console.log(errors)
    })
  }
}

removeStock() 看起来像这样:

export const removeStock = (stock_name) => {
  return {
    type: 'REMOVE_PINNED_STOCK',
    stock_name: stock_name
  }
}

与我的 reducer 中的“REMOVE_PINNED_STOCK”操作相对应的 case 语句如下所示:

reducer.js

  case 'REMOVE_PINNED_STOCK':
    return {
      ...state, 
      stocksData: {
      ...state.stocksData.delete((stock) => stock.name === action.stock_name)
      }
  }

我不知道为什么我不能在我的deletePinnedStock() 函数中调度removeStock() 函数。在我的 action.js 文件的其他地方，我调度函数没有任何问题。

编辑#1: deletePinnedStock 在我的组件中定义如下:

stockCard.js

import React, { Component } from 'react';
import { connect } from 'react-redux';
import { fetchPinnedStocks, deletePinnedStock, fetchStockData } from 
'../redux/modules/Stock/actions';
import '../styles/spin.css';
import Panel from 'react-uikit-panel';

class StockCard extends Component {

render() {
    const user_id = localStorage.getItem('currentUser_id') 
    const stock = this.props.stock //should be the stockObj keyed by name
    if (!stock) { 
        return null 
    } else {
    return (
        <Panel col='1-2' box title={stock.name} margin='bottom' context='primary'>
            <div>
                Open: {stock.openingPrice}
            </div>
            <div>
                Close: {stock.closingPrice}
            </div>
            <div>
                Low: {stock.low}
            </div>
            <div>
                High: {stock.high}
            </div>
            <div>
                Trading Volume: {stock.volume}
            </div>
            <button type="submit" 
            onClick={deletePinnedStock(user_id, stock.name, stock.id)}>Remove</button>
        </Panel>)
    }
  }
}

function mapStateToProps(state) {
  return {
    currentUser: state.auth.currentUser,
    stocksData: state.stock.stocksData 
  }
}

export default connect(mapStateToProps, { fetchPinnedStocks, 
deletePinnedStock, fetchStockData })(StockCard); 

Answer 1

通过直接调用 deletePinnedStock，您只是将其作为函数调用，而不是将其分派(dispatch)到 redux 存储。当您将操作创建者传递给 connect() 时，它会作为 Prop 添加到您的组件中，并且该 Prop 是映射到 dispatch 的 Prop 。

简而言之，替换

onClick={deletePinnedStock(user_id, stock.name, stock.id)}

与

onClick={this.props.deletePinnedStock(user_id, stock.name, stock.id)}