React中使用react-router-dom路由

安装
首先进入项目目录，使用npm安装react-router-dom：
npm install react-router-dom --save-dev //这里可以使用cnpm代替npm命令
新建router.js
import React from 'react';
import {
     HashRouter, Route, Switch} from 'react-router-dom';
import Home from '../home';
import Detail from '../detail';


const BasicRoute = () => (
    <HashRouter>
        <Switch>
            <Route exact path="/" component={
     Home}/>
            <Route exact path="/detail" component={
     Detail}/>
        </Switch>
    </HashRouter>
);


export default BasicRoute;
index.js 入口页
import React from 'react';
import ReactDOM from 'react-dom';
import Router from './router/router';

ReactDOM.render(
  <Router/>,
  document.getElementById('root')
);
通过a标签跳转
import React from 'react';


    export default class Home extends React.Component {
     
        render() {
     
            return (
                <div>
                <a href='#/detail'>去detail</a>
            </div>
        )
    }
}
通过函数跳转
router.js 修改
...
import {
     HashRouter, Route, Switch, hashHistory} from 'react-router-dom';
...
<HashRouter history={
     hashHistory}>
...
跳转页
export default class Home extends React.Component {
     
    constructor(props) {
     
        super(props);
    }
    
    
    render() {
     
        return (
            <div>
                <a href='#/detail'>去detail</a>
                <button onClick={
     () => this.props.history.push('detail')}>通过函数跳转</button>
            </div>
        )
    }
}
url传参
router.js 修改
...
<Route exact path="/detail/:id" component={
     Detail}/>
...
<Link to="/detail/123">用户</Link>
hashHistory.push("/user/123");
detail.js中使用this.props.match.params获取url传过来的参数：
...
componentDidMount() {
     
    console.log(this.props.match.params);
}
...
隐式传参
import React from 'react';


export default class Home extends React.Component {
     
    constructor(props) {
     
        super(props);
    }
    
    
    render() {
     
        return (
            <div>
                <a href='#/detail/3'>去detail</a>
                    <button onClick={
     () => this.props.history.push({
     
                        pathname: '/detail',
                        state: {
     
                            id: 3
                        }
                })}>通过函数跳转</button>
            </div>
        )
    }
}
在detail.js中，就可以使用this.props.history.location.state获取home传过来的参数：
state方式依然可以传递任意类型的数据，而且可以不以明文方式传输。
var data = {
     id:3,name:sam,age:36};
var path = {
     
  pathname:'/user',
  query:data,
}
var data = this.props.location.query;
query方式可以传递任意类型的值，但是页面的URL也是由query的值拼接的，URL很长
componentDidMount() {
     
    //console.log(this.props.match.params);
    console.log(this.props.history.location.state);
}
其他函数
replace
有些场景下，重复使用push或a标签跳转会产生死循环，为了避免这种情况出现，react-router-dom提供了replace。在可能会出现死循环的地方使用replace来跳转：


this.props.history.replace('/detail');
goBack
场景中需要返回上级页面的时候使用：

this.props.history.goBack();
嵌套路由
import React from 'react';
import './MainLayout.scss';

const {
      Header, Sider, Content } = Layout;


export default class MainLayout extends React.Component {
     

    render() {
     
        return (
            <div className='main-layout'>
                父组件
            </div>
        );
    }
}
import React, {
     useState} from 'react';
import {
     Modal, Select} from "antd";
import {
     connect} from 'react-redux';
import {
     addCount} from '../../servers/home';


function Home(props) {
     
    const [visible, setVisible] = useState(false);
    const {
     countNum: {
     count}, dispatch} = props;

    return (
        <div>
            子组件
        </div>
    )
}
router.js
export default Home;
import React from 'react';
import {
     HashRouter, Route, Switch} from "react-router-dom";
import Home from '../pages/Home/Home';
import MainLayout from '../layout/MainLayout';

const BasicRouter = () => (
    <HashRouter>
        <Switch>
            <Route path="/index" component={
     
                <MainLayout>
                  <Route exact path="/" component={
     Home}/>
                  <Route exact path="/index" component={
     Home}/>
                  <Route path="/index/home" component={
     Home}/>
                </MainLayout>
             }/>
        </Switch>
    </HashRouter>
);


export default BasicRouter;

//可能出现的问题
1、Attempted import error: 'hashHistory' is not exported from 'react-router'.


import {
      HashRouter as Router, Route, hashHistory } from 'react-router-dom'
页面就会报错Attempted import error: 'hashHistory' is not exported from 'react-router'.

//原因react-router4现在不支持hashHistory了，解决办法如下：

import createHashHistory from 'history/createHashHistory';
const hashHistory = createHashHistory();
//但是又提示Warning: Please use require("history").createHashHistory instead of require("history/createHashHistory"). Support for the latter will be removed in the next major release.如下改一下：
import {
      createHashHistory } from 'history';
const hashHistory = createHashHistory();
//此时 Warning:  ignores the history prop. To use a custom history, use import { Router } instead of import { HashRouter as Router }.
//OK，暂时解决眼前的问题。


2、Cannot read property 'push' of undefined
在父子组件上,在父组件调用子组件定义的跳转事件时,要传递history

父组件

<BottomBar
    history={
     this.props.history}
/>
子组件

<div
    onClick={
     ()=>{
     
        this.props.history.push(`/path`);
    }}
>
    child
</div>