react进入路由前获取数据_react之传递数据的几种方式props传值、路由传值、状态提升、redux、context...

父组件：

import { Route, Switch, Redirect } from 'react-router-dom'

class App extends Component {

render() {

return (

);

}

export default App;

子组件：

{this.props.match.params.shopName}

{this.props.match.params.shopNote}篇笔记

关注

方法二：

var data = {id:0,name:'lili',age:16};

data=JSON.stringify(data);var path = `/user/${data}`;用户

var data = this.props.location.query;var {id,name,age} = data;

3、状态提升：其原理是两个或者多个组件需要共享的数据放在他们公共的祖先身上，通过props实现共享

L：父组件为

子组件为

在父组件中调用子组件：

以此类推。

4、redux

已我自己写的一个小demo为例子：

大概项目大概如第二张图，具体应用体现在goodDetail文件夹内

新建一个store文件夹，做一个数据处理的汇总

store/redecers.js

import { combineReducers } from'redux'import shop from'pages/shop/reducer'import car from'pages/goodDetail/reducer'exportdefaultcombineReducers({

shop,

car

})

store/index.js

import { createStore, applyMiddleware } from 'redux'import thunk from'redux-thunk'import reducers from'./reducers'const store=createStore(reducers, applyMiddleware(thunk))

exportdefault store

goodDetail/actionType.js

export const GET_CAR_DATA = 'car/get_car_data'

goodDetail/actionCreator.js

import { GET_CAR_DATA } from './actionType'export const loadCarDataSync= (goods) =>{//console.log(goods)

return{

type: GET_CAR_DATA,

goods:goods

}

export const loadCarDataAsync= (dispatch,obj) =>{//console.log(1)

//console.log(obj)

return () =>{

dispatch(loadCarDataSync(obj))

}

goodDetail/reducer.js(处理数据)

import {GET_CAR_DATA} from './actionType'const defaultState={

goods:[{

shopName:"豌豆公主海外美妆集合店",

he:[

{ image:"https://img.xiaohongshu.com/items/4d9747c4f9c03b7c2eafc4d066061968@_320w_320h_1e_1c_0i_90Q_1x_2o.jpg",

introduce:"clé de Peau Beauté肌肤之钥沁肌紧肤水磨精华液 170ml",

kuSave:296161,

num:4,

price:609}

]

}

]

}

exportdefault (state=defaultState, action) =>{if (action.type ===GET_CAR_DATA) {if(!!state.goods){

const obj= state.goods.find(v => v.shopName ===action.goods.shopName )if(!!obj){

const same= obj.he.find(i => i.introduce === action.goods.he[0].introduce )

console.log(obj)if(!!same){

same.num++;

}else{

obj.he.push(...action.goods.he)

}return{

goods: [...state.goods]

}

}else{return{

goods: [...state.goods,action.goods]

}

}else{return{

goods: [action.goods]

}

}returnstate

}

整个项目最外面的index.html中引入

import store from './store'

在goodDetail/goodDetai.js中

import { connect } from 'react-redux'import {

Link,

withRouter

} from'react-router-dom'import { loadCarDataAsync } from'./actionCreator'const mapState= (state) =>{//console.log(state)

return{

goods: state.car.goods

}

const mapDispatch= (dispatch) =>{return{

loadCategories (obj) {//console.log(obj)

dispatch(loadCarDataAsync(dispatch,obj))

}

中间代码省略，在你需要的地方调用this.props.loadCategories(

{

shopName:this.state.good.vendor_name,

he:[{

image:this.state.good.image,

introduce:this.state.good.desc,

price:this.state.good.discount_price,

kuSave:this.state.good.fav_info.fav_count,

num:Number(this.refs.goodNum.value)

}]

}

) (参数可传可不传，不传的话，其余对应的地方记得修改)

exportdefault withRouter(connect(mapState, mapDispatch)(GoodDetail))

5、context

不合适修改数据

更适合共享数据

getChildContext()

祖先组件：

1>import PropsTypes from 'prop-types'

2>static childCOntextTypes={

XX:PropsTypes.string

}

3>getChildContext(){

return {XX:xx}

}

4>引入一个子组件

子组件接收：

this.context.XX