react路由重定向时 exact的作用 报错Warning: You tried to redirect to the same route you're currently on: "/index"

//Redirect重定向
class RouterIndex extends Component{
    render(){
        return (
            <Switch>
                <Route path="/" render={()=>(
                    <Redirect to="/index" />
                    
                )} />
                
                <Route path="/index" component={Index} />
                <Route path="/book" component={Book} />
                <Route path="/user" component={User} />
                <Route path="/about" component={About} />
                <Route path="/details" component={Details} />

            </Switch>
        )
    }
}
export default RouterIndex;

  报错Warning: You tried to redirect to the same route you're currently on: "/index"，修改路径时i无法显示页面内容

在需要重定向的组件里添加exact就可解决

//Redirect重定向
class RouterIndex extends Component{
    render(){
        return (
            <Switch>
                <Route exact path="/" render={()=>(
                    <Redirect to="/index" />
                    
                )} />
                
                <Route path="/index" component={Index} />
                <Route path="/book" component={Book} />
                <Route path="/user" component={User} />
                <Route path="/about" component={About} />
                <Route path="/details" component={Details} />

            </Switch>
        )
    }
}
export default RouterIndex;