react后端请求数据的实现方法：1、在package.json中配置“ "proxy":"http://localhost:5000"”；2、在src目录下创建“setupProxy.js”文件；3、调用“setupProxy.js”中配置的功能，代码如“createProxyMiddleware('/api2',{target:...}”。
本教程操作环境：Windows10系统、react18.0.0版、Dell G3电脑。
react后端请求数据怎么实现？
react-ajax请求后台数据方法
"proxy":"http://localhost:5000"
getStudentData = () => {
axios.get('/students').then(
(result) => { console.log(result.data); },
(reason) => { console.log(reason); })
}**优点：**配置简单，前端请求资源不需要任何前缀
**缺点：**不能配置多个代理服务器
第一步：webpack配置了调用setupProxy.js中配置的功能
setupProxy.js
第二步：配置
//const proxy=require("http-proxy-middleware") :视频中请求的包，引用它出现了无法访问的问题//应该使用以下写法*******const { createProxyMiddleware } = require("http-proxy-middleware");module.exports=function(app){
app.use(
createProxyMiddleware('/api1',{//遇见/api1前缀的请求，就会触发该代理配置
target:"http://localhost:5000",//请求转发给谁
changeOrigin:true,//控制服务器收到的请求头中Host字段的值：host就是主机名+端口号
//true:后端接收到的host：localhost:5000
//false:后端接收到的host：localhost:3000
//系统默认为false，一般会设为true
pathRewrite:{"^/api1":""}//重写请求路径（必须要写）
//不写：后台接收到的请求路径：/api1/student
//写了：后台请求的路径：/student
}),
createProxyMiddleware('/api2',{
target:"http://localhost:5001",
changeOrigin:true,
pathRewrite:{"^/api2":""}
}),
)}解决问题链接：https://www.csdn.net/tags/OtTaIg0sNzE3OC1ibG9n.html
App.jsx
import React, { Component } from 'react'
import Search from './components/Search'
import List from './components/List'
import './App.css'
export default class App extends Component {
state={users:[]}
getSearchResult=(result)=>{
this.setState({users:result})
}
render() {
return (
<div className="container">
<Search getSearchResult={this.getSearchResult}/>
<List users={this.state.users}/>
</div>
)
}
}Search.jsx
import React, { Component } from 'react'
import axios from 'axios'
import './index.css'
export default class Search extends Component {
search = () => {
//获取输入框中的值
const { value } = this.keyWordElement;
//发送请求
axios.get(`/api1/search/users?q=${value}`).then(
result => {
this.props.getSearchResult(result.data.items)
},
reason => {
console.log(reason);
})
}
render() {
return (
<section className="jumbotron">
<h3 className="jumbotron-heading">搜索github用户</h3>
<div>
<input ref={c => this.keyWordElement = c} type="text" placeholder="enter the name you search" /> <button onClick={this.search}>搜索</button>
</div>
</section>
)
}
}List.jsx
import React, { Component } from 'react'
import './index.css'
export default class List extends Component {
render() {
return (
<div className="row">
{this.props.users.map(item=>{
return <div key={item.id} className="card">
<a href={item.html_url} target="_blank">
<img src={item.avatar_url} style={{ width: "100px" }} />
</a>
<p className="card-text">{item.login}</p>
</div>
})}
</div>
)
}
}PubSubJs：
pubsub-js:就是用来实现发布订阅的，可以把它看过vue中的eventBus，看作是函数的载体
订阅方：创建一个函数，并且将这个函数传给pubsub做托管
var token=PubSub.subscribe("myTopic",myFunction[托管的函数])//token，是当前订阅函数的唯一id，可以用来取消订阅发布方：发布的意思就是通过调用订阅方指定的函数，实现传参或执行操作功能
PubSub.publish('myTopic','需要发送给订阅者的内容')第一步：添加pubsub-js
yarn add pubsub-js
**第二步：**在组件中导入
import PubSub from 'pubsub-js'
**第三步：**调用PubSub订阅函数(一般是在componentDidMount钩子函数中订阅)
componentDidMount(){
this.token=PubSub.subscribe("changeState",this.changeStateObj)
}import React, { Component } from 'react'
import PubSub from 'pubsub-js'
import './index.css'
export default class List extends Component {
state={
users:[],//拿到的用户信息
isFirst:true,//是否第一次访问
isLoading:false,//是否正在加载
err:"",//返回的错误信息
}
changeStateObj=(msg,value)=>{
this.setState(value)
}
componentDidMount(){
this.token=PubSub.subscribe("changeState",this.changeStateObj)
}
componentWillUnmount(){
PubSub.unsubscribe(this.token)
}
render() {
let {users,isFirst,isLoading,err}=this.state
return (
{
isFirst?输入搜索内容搜索用户
:
isLoading?Loading...
:
err?{err}
:
users.map(item=>{
return
{item.login}
})}
)
}
}import React, { Component } from 'react'
import axios from 'axios'
import './index.css'
import PubSub from 'pubsub-js'
export default class Search extends Component {
search = () => {
//获取输入框中的值
const { value } = this.keyWordElement;
PubSub.publish('changeState',{isFirst:false,isLoading:true})
//发送请求
axios.get(`/api1/search/users2?q=${value}`).then(
result => {
PubSub.publish('changeState',{isLoading:false,users:result.data.items})
},
reason => {
PubSub.publish('changeState',{isLoading:false,err:reason.message})
})
}
render() {
return (
<section className="jumbotron">
<h3 className="jumbotron-heading">搜索github用户</h3>
<div>
<input ref={c => this.keyWordElement = c} type="text" placeholder="enter the name you search" /> <button onClick={this.search}>搜索</button>
</div>
</section>
)
}
}import React, { Component } from 'react'
import Search from './components/Search'
import List from './components/List'
import './App.css'
export default class App extends Component {
render() {
return (
<div className="container">
<Search />
<List/>
</div>
)
}
}
let getData=async()=>{
try{
let result=await fetch(url);
let data=await result.json();
}catch(error){
console.log('请求错误',error)
}
}以上是react后端请求数据怎么实现的详细内容。更多信息请关注PHP中文网其他相关文章！
