react-router中withRouter的作用

  withRouter是react-router的一个高阶组件，可获取history
  render时会把match, location和history传入props

用法1

import React,{Component} from 'react'
import {withRouter} from 'react-router-dom'
class App extends Component{
    console.log(this.props);  // {match: {…}, location: {…}, history: {…}…}
    render(){
      return (<div className='app'></div>)
    }
}
export default withRouter(App);  

用法2

import React,{Component} from 'react'
import {withRouter} from 'react-router-dom'
@withRouter
class App extends Component{
    console.log(this.props);  // {match: {…}, location: {…}, history: {…}…}
    render(){
      return (<div className='app'></div>)
    }
}
export default App; 

• 注释
  @withRouter 属于装饰器语法需要额外配置
  执行：npm install babel-plugin-transform-decorators-legacy --save-dev
  具体实现请查看react @装饰器相关文档
  脚手架的在packag的babel中配置

{
    "plugins":[
        "transform-decorators-legacy"
    ]
}

非脚手架的在webpack.config.js的jsx语法babel-loader中配置

 plugins: [
            'transform-decorators-legacy'
]