Reactjs 未定义React this.context.router
在我的主页组件中,未定义this.context.router。我正在使用以下依赖项:Reactjs 未定义React this.context.router,reactjs,material-ui,Reactjs,Material Ui,在我的主页组件中,未定义this.context.router。我正在使用以下依赖项: "@material-ui/core": "^3.9.3", "@material-ui/icons": "^3.0.2", "history": "^4.9.0", "moment": "^2.24.0", "prop-types": "^15.7.2", "react": "^16.8.6", "react-dom": "^16.8.6", "react-router-dom": "^5.0.0", "r
"@material-ui/core": "^3.9.3",
"@material-ui/icons": "^3.0.2",
"history": "^4.9.0",
"moment": "^2.24.0",
"prop-types": "^15.7.2",
"react": "^16.8.6",
"react-dom": "^16.8.6",
"react-router-dom": "^5.0.0",
"react-scripts": "2.1.8",
"react-swipeable-views": "^0.13.1"
我的index.js是:
import React from 'react';
import ReactDOM from 'react-dom';
import {Switch, Router, Route, BrowserRouter } from 'react-router-dom';
import {MuiThemeProvider, createMuiTheme } from '@material-ui/core/styles';
import * as serviceWorker from './serviceWorker';
import UserApp from 'components/App.js';
ReactDOM.render((
<MuiThemeProvider theme={createMuiTheme({typography: { useNextVariants: true, },})}>
<BrowserRouter>
<Switch>
<Route path='/' component={UserApp} />
</Switch>
</BrowserRouter>
</MuiThemeProvider>
), document.getElementById('root'));
serviceWorker.register();
从“React”导入React;
从“react dom”导入react dom;
从“react Router dom”导入{Switch,Router,Route,BrowserRouter};
从'@material ui/core/styles'导入{MuiThemeProvider,createMuiTheme};
将*作为serviceWorker从“/serviceWorker”导入;
从“components/App.js”导入UserApp;
ReactDOM.render((
),document.getElementById('root');
register();
组件/App.js的内容包括:
import React, { Component } from 'react';
import Header from 'components/layout/Header.js';
import Footer from 'components/layout/Footer.js';
import Main from 'components/layout/Main.js';
class App extends Component {
constructor(props) {
super(props);
this.state = {
navOpen: false
};
}
openLeftNav=()=>{}
render() {
return (
<div className="site-app">
<Header {...this.props} openLeftNav={this.openLeftNav} />
<Main />
<Footer />
</div>
);
}
}
export default App;
import React,{Component}来自'React';
从“components/layout/Header.js”导入标题;
从“components/layout/Footer.js”导入页脚;
从“components/layout/Main.js”导入Main;
类应用程序扩展组件{
建造师(道具){
超级(道具);
此.state={
navOpen:错误
};
}
openLeftNav=()=>{}
render(){
返回(
);
}
}
导出默认应用程序;
Main是我们的内部应用程序路由文件。Main.js的结构是:
import React from 'react';
import { Switch, Route } from 'react-router-dom';
import HomePage from 'components/app/account/Home.js';
const Main = () => (
<main>
<Switch>
<Route exact path='/' component={HomePage}/>
</Switch>
</main>
);
export default Main;
从“React”导入React;
从“react router dom”导入{Switch,Route};
从“components/app/account/Home.js”导入主页;
常量Main=()=>(
);
导出默认主;
我的Home.js文件是:
import React from 'react';
import PropTypes from 'prop-types';
import classNames from "classnames";
import withStyles from "@material-ui/core/styles/withStyles";
import landingPageStyle from "assets/jss/landingPage.jsx";
class Home extends React.Component {
constructor(props, context) {
super(props, context);
this.state = {
expanded: null,
}
}
componentDidMount() {}
testFunction=()=>{
console.log(this.context);
this.context.router.history.push('/test-page');
}
render() {
return (
<div>
<Button color="primary" onClick={this.testFunction}>Click Me</Button>
</div>
)
}
}
Home.contextTypes = {
router: PropTypes.object.isRequired
};
export default withStyles(landingPageStyle)(Home);
从“React”导入React;
从“道具类型”导入道具类型;
从“类名”中导入类名;
从“@material ui/core/styles/withStyles”导入withStyles;
从“assets/jss/landingPage.jsx”导入landingPageStyle;
类Home扩展了React.Component{
构造函数(道具、上下文){
超级(道具、背景);
此.state={
扩展:null,
}
}
componentDidMount(){}
testFunction=()=>{
log(this.context);
this.context.router.history.push('/testpage');
}
render(){
返回(
点击我
)
}
}
Home.contextTypes={
路由器:PropTypes.object.isRequired
};
导出默认样式(landingPageStyle)(主页);
我想有条件地使用this.context.route导航,有人能帮我解释一下为什么this.context.router未定义吗?
这段代码以前在react[v16.3]react router dom[v4.2.2]和material ui[v1.1.0]的早期版本中使用过,但现在它不起作用。我也遇到过同样的情况,我开始使用react router dom提供的链接
import { Link } from 'react-router-dom';
import Button from '@material-ui/core/Button';
<Button component={Link} to="/test-page">
About
</Button>
您需要将
withRouter
hoc包装到您的组件上,以访问历史道具-是否需要使用withRouter?我只是想知道它是如何工作在我以前的项目有相同的代码没有使用withRouter?我不知道你是如何在你的上一个项目,但据我所知,是的。另外,我也不知道上下文是从哪里来的。我以前的项目是相同的编码结构,只是版本不同——react[v16.3]react router dom[v4.2.2]和material ui[v1.1.0]。总之,我开始使用withRouter,它工作了。但我还是想知道原因,如果你将来有任何答案,那将帮助我肖恩·亚普。非常感谢。
...
import { withRouter } from 'react-router-dom';
class Home extends React.Component {
testFunction=()=> this.props.history.push('/test-page');
...
}
export default withStyles(landingPageStyle)(withRouter(Home));