Question

我正在尝试在React Router中发送参数并遇到错误

参考代码在我的Route.js中，我添加了browserRouter和Route

function AppRoute() {
    const classes = useStyles();
    return (
        <BrowserRouter>
            <div className={classes.root}>
                <div className='App-header'>

                    <Grid container justify="center" className={classes.root} spacing={2} alignItems="center">
                        <Grid item xs={3}>

                            <Paper className={classes.paper} >
                                <Link to='/'>Dashboard</Link>
                            </Paper>
                        </Grid>

                        <Grid item xs={3}>
                            <Paper className={classes.paper} >
                                <Link to='/create'>Create</Link>
                            </Paper>
                        </Grid>
                        <Grid item xs={3}>
                            <Paper className={classes.paper} >
                                <Link to="/edit/john">Edit</Link>
                            </Paper>
                        </Grid>
                        <div>
                            <Switch>
                                <Route exact path="/" component={Dashboard} exact={true} />
                                <Route exact path="/create" component={Create} />
                                <Route path="/edit/:name">
                                    <Edit />
                                </Route>
                            </Switch>
                        </div>
                    </Grid>



                </div>
            </div>

        </BrowserRouter>


    )
}

Edit.js

function Edit() {
    const { name } = useParams();
    return (
        <div>
            Name - {name}
        </div>
    )
}

Answer 1

从您得到的错误中，我们可以得出以下结论：

Cannot read property 'match' of undefined

这发生在第40行，如您从屏幕截图中所见。

const match = useContext(Context).match

这意味着呼叫的这一部分正在返回undefined：

useContext(Context) === undefined

换句话说，这意味着Context.Provider在组件树的该点不可用。

您应该在<Route/>呈现的组件内部调用此函数。否则它将找不到Context，您将收到此错误。仔细检查。

来自：https://reactrouter.com/web/api/Hooks/useparams

import React from "react";
import ReactDOM from "react-dom";
import {
  BrowserRouter as Router,
  Switch,
  Route,
  useParams
} from "react-router-dom";

function BlogPost() {
  let { slug } = useParams();       // IT'S CALLED INSIDE BlogPost
  return <div>Now showing post {slug}</div>;
}

ReactDOM.render(
  <Router>
    <Switch>
      <Route exact path="/">
        <HomePage />
      </Route>
      <Route path="/blog/:slug">
        <BlogPost />                {/* <<< AND BlogPost IS RENDERED INSIDE A <Route/> */}
      </Route>
    </Switch>
  </Router>,
  node
);

无法读取useParams处未定义的属性“匹配”-React Hooks

1 个答案: