我该如何解决这个问题 我尝试搜索匹配路线，但没有显示任何内容？

Question

this my single product page

    import React from "react";
    import { Link } from "react-router-dom";
    import Rating from "../components/Rating";
    import Product from "../Data";
    import { Row, Button, Col, Image, ListGroup, Card } from "react-bootstrap";
    // import PropTypes from 'prop-types';* 

This where I tired to find the match id and render the product with match id

    const Products = ({match}) => {
      const product = Product.find((p) => p._id === match.params.id);
      return (
        <>
          <Link className="btn btn-dark my-3" to="/" />
          Go Back
          <Row>
            <Col md={6}>
              <Image src={product.img} fluid />
            </Col>
            <Col md={3}>
              <ListGroup variant="flush">
                <ListGroup.Item>
                  <h3>{product.name}</h3>
                </ListGroup.Item>
              </ListGroup>
              <ListGroup.Item>
                <Rating
                  value={product.Rating}
                  text={`${product.numReviews}`}
                />
              </ListGroup.Item>
              <ListGroup.Item>
                <p>Description:{product.desc}</p>
              </ListGroup.Item>
              <ListGroup.Item>
                <p>price: $ {product.price}</p>
              </ListGroup.Item>
            </Col>
            <Col md={3}>
              <Card>
                <ListGroup variant="flush">
                  <ListGroup.Item>
                    <Row>
                      <Col>Price:</Col>
                      <Col>
                        <strong>$ {product.price}</strong>
                      </Col>
                    </Row>
                  </ListGroup.Item>
                  <ListGroup.Item>
                    <Row>
                      <Col>Status:</Col>
                      <Col>
                        {product.countInStock > 0 ? "In Stock" : "Out Of Stock"}
                      </Col>
                    </Row>
                  </ListGroup.Item>
                  <ListGroup.Item>
                    <Button
                      className="btn btn-primary"
                      type="button"
                      disabled={product.countInStock === 0}
                    >
                      Add To Cart
                    </Button>
                  </ListGroup.Item>
                </ListGroup>
              </Card>
            </Col>
          </Row>
        </>
      );
    };

    

export default Products;

This is my single product screen

import Products from "./pages/Products";
const App = () => {
  return (
    <BrowserRouter>
      <Header />
      <main className="py-3">
        <Container>
          <Routes>
            <Route  index element={<Home />} />
            <Route path="product" element={<Products />} />
            <Route path=":id" element={<Products />} />

          </Routes>
        </Container>        
      </main>
      <Footer />
    </BrowserRouter>
  );
};

export default App;

Answer 1

Try this:

<Routes>
    <Route path="/" element={<Home />} />
    <Route path="product/:id" element={<Products />} />
</Routes>

Your product page:

const {id} = useParam() // we can destructure out the id

const fetchProduct = async (id) => {
    const resultFromServer = await fetch(`url/${id}`)
    const dataFromServer = await resultFromServer.json()
    // with the data, now we can store it in useState or Context api
    // depends on your implementation, and show it to the client
}

useEffect(() => {
    if(id) fetchProduct(id) // Fetch product based on url id
},[]);  

Answer 2

Issue

In react-router-dom v6 the Route components no longer have route props ( history , location , and match ), and the current solution is to use the React hooks "versions" of these to use within the components being rendered.

In other words, props.match is undefined. This should also be clear since no props are passed to Products .

<Route path=":id" element={<Products />} /> // <-- no props passed to Products

Solution

Use the useParams hook to access the id route path param in the Products component. Don't forget that Array.prototype.find can potentially return undefined if no element matches the predicate, so your UI code should handle this case. ( avoids "undefined access of X" exceptions )

Example:

import { Link, useParams } from 'react-router-dom';

const Products = () => {
  const { id } = useParams();

  const product = Product.find((p) => p._id === id);

  if (!product) return "No matching product found.";

  return (
    <>
      ...
    </>
  );
};