Javascript 如何在正在使用的同一组件中访问MapStateTops?
我有以下代码示例:Javascript 如何在正在使用的同一组件中访问MapStateTops?,javascript,reactjs,redux,Javascript,Reactjs,Redux,我有以下代码示例: import React, {Component} from 'react' import { FontAwesomeIcon } from '@fortawesome/react-fontawesome'; import {connect} from 'react-redux' import axios from '../../axios' import classes from './List.module.css' import {Button,Lis
import React, {Component} from 'react'
import { FontAwesomeIcon } from '@fortawesome/react-fontawesome';
import {connect} from 'react-redux'
import axios from '../../axios'
import classes from './List.module.css'
import {Button,ListGroup} from 'reactstrap'
import Input from '../UI/Input/Input'
import Items from './Items/Items'
class List extends Component{
componentWillMount() {
axios.get('/list/items.json')
.then(response=>{
console.log("response.data")
console.log(response.data)
this.props.initialState(response.data)
}).catch(error=>console.log(error))
}
render(){
let inputElement = null
if(this.props.input){
inputElement=(
<Input
changedName={this.props.changedName}
changedDesc={this.props.changedDesc}
addOrEdit={this.props.addItem}
nameInput={this.props.state.nameInput}
descInput={this.props.state.descInput}
buttonText={this.props.state.buttonText}/>
)
}
let editElement = null
if(this.props.state.edit){
editElement=(
<Input
changedName={this.props.changedName}
changedDesc={this.props.changedDesc}
addOrEdit={this.props.editItem}
nameInput={this.props.state.nameInput}
descInput={this.props.state.descInput}
buttonText={this.props.state.buttonText}/>
)
}
let itemElement = null
if(this.props.items && this.props.items.length !== 0 ){
itemElement = this.props.items.map((i,index)=>{
return <Items
className={classes.items}
id={index}
name={i.itemName}
key={index}
deleteClicked={()=>this.props.deleteItem(index)}
itemIndex={()=>this.props.itemIndexChanger(index)}
editInput={()=>this.props.editItemHandler(index)}
editIndex={this.props.state.editIndex}
editElement={editElement}/>
})
}else{
itemElement = <h4 className={classes.items}>Please add an Item</h4>
}
return(
<div className={classes.items}>
<ListGroup>
{itemElement}
</ListGroup>
<hr className={classes.hr}/>
<Button
className={classes.button}
onClick={this.props.toggleInputHandler}
size="sm"
outline color='info'>
Add Items
<FontAwesomeIcon icon='plus'/>
</Button>
{inputElement}
</div>
)
}
}
const mapStateToProps = (state) =>{
return{
items:state.items,
input:state.input,
state:state
}
}
function fetchData(){
console.log(this.props.state)
}
const mapDispatchToProps = dispatch=>{
return{
toggleInputHandler:()=>dispatch({type:'TOGGLE_INPUT_HANDLER'}),
changedName:(event)=>dispatch({type:'CHANGED_NAME', payload:event.target.value}),
changedDesc:(event)=>dispatch({type:'CHANGED_DESC',payload:event.target.value}),
addItem:()=>{return(dispatch({type:'ADD_ITEM'}))},
deleteItem:(index)=>dispatch({type:'DELETE_ITEM',index:index}),
editItemHandler:(index)=>dispatch({type:'EDIT_ITEM_HANDLER',index:index}),
editItem:()=>dispatch({type:'EDIT_ITEM'}),
itemIndexChanger:(index)=>dispatch({type:'CHANGE_ITEM_INDEX',index:index}),
initialState:(value)=>dispatch({type:'SET_STATE',payload:value})
};
}
export default connect(mapStateToProps, mapDispatchToProps)(List)
import React,{Component}来自“React”
从'@fortawesome/react fontawesome'导入{FontAwesomeIcon};
从“react redux”导入{connect}
从“../../axios”导入axios
从“./List.module.css”导入类
从“reactstrap”导入{按钮,列表组}
从“../UI/Input/Input”导入输入
从“./Items/Items”导入项目
类列表扩展组件{
组件willmount(){
get('/list/items.json'))
。然后(响应=>{
console.log(“response.data”)
console.log(response.data)
this.props.initialState(response.data)
}).catch(错误=>console.log(错误))
}
render(){
让inputElement=null
if(此.props.input){
输入元素=(
)
}
让editElement=null
if(this.props.state.edit){
编辑元素=(
)
}
设itemElement=null
if(this.props.items&&this.props.items.length!==0){
itemElement=this.props.items.map((i,索引)=>{
返回此.props.deleteItem(索引)}
itemIndex={()=>this.props.itemIndexChanger(index)}
editInput={()=>this.props.editItemHandler(索引)}
editIndex={this.props.state.editIndex}
editElement={editElement}/>
})
}否则{
itemElement=请添加一个项目
}
返回(
{itemElement}
添加项目
{inputElement}
)
}
}
常量mapStateToProps=(状态)=>{
返回{
项目:state.items,
输入:state.input,
州:州
}
}
函数fetchData(){
console.log(this.props.state)
}
const mapDispatchToProps=调度=>{
返回{
toggleInputHandler:()=>dispatch({type:'TOGGLE\u INPUT\u HANDLER'}),
changedName:(event)=>dispatch({type:'CHANGED_NAME',payload:event.target.value}),
changedDesc:(event)=>dispatch({type:'CHANGED_DESC',payload:event.target.value}),
addItem:()=>{return(dispatch({type:'ADD_ITEM'}))},
deleteItem:(index)=>dispatch({type:'DELETE_ITEM',index:index}),
editItemHandler:(index)=>dispatch({type:'EDIT_ITEM_HANDLER',index:index}),
editItem:()=>dispatch({type:'EDIT_ITEM'}),
itemIndexChanger:(index)=>dispatch({type:'CHANGE\u ITEM\u index',index:index}),
initialState:(值)=>dispatch({type:'SET_STATE',payload:value})
};
}
导出默认连接(MapStateTrops、mapDispatchToProps)(列表)
据推测,在调用函数fetchdata后,它应该console.log我在mapStateProps中设置的状态,但是它给出了未定义的,即使该状态根本没有定义。。。
我的意图是将此fetchdata函数设置为axios put请求,但我无法执行此操作,因为我要发送的数据(即我在MapStateTops中设置的“项”)返回未定义,这意味着我无法访问MapStateTops中的内容
你们知道我做错了什么吗
感谢您的关注看来fetchData函数不在组件列表中。因此,您无法访问组件的
此
,您将获得“无法读取未定义属性'props'”。我认为我们需要此文件的其余部分此
可以根据调用函数的位置进行更改。在类“body”中移动获取数据
方法。请提供完整的代码。。有了list组件来回答您的问题,正如你们所看到的,这里有完整的代码,我可以在render方法内部访问mapStateToProps属性,但不能在它之外。。。