如何将变量从一个组件传递到另一个组件？

Question

I'd like to pass the name variable in SingerBox.js to the Album component so I can display an artist's albums. When I print props.name, it's undefined. How do I pass it properly?

SingerBox.js

import React, { Component } from "react";
import Modal from "react-bootstrap/Modal";
import ImageNotFound from "../../ImageNotFound.jpg";
import "../../App.css";
import { Link } from "react-router-dom";

import Albums from "../Albums/Albums";

const SingerCard = (props) => {
  const { images, name, artists } = props;

  //check if the image array is empty since some artists' image data provided by the API call are empty
  const singer_img = images.length === 0 ? ImageNotFound : images[0].url;

  return (
    <>
      <Link to="/albums" onClick={() => <Albums name={name} />}>
        <div className="box">
          <div>
            <img className="singer-img" src={singer_img} alt="Card image" />
            {name}
          </div>
        </div>
      </Link>
    </>
  );
};

export default SingerCard;

Albums.js

import React, { Component } from "react";

const Albums = (props) => {
  return <div style={{ color: "white" }}> {`${props.name}'s albums`}</div>;
};

export default Albums;

The result is "undefined's albums".

Answer 1

In your case, you attempt to pass the variable through the <Link> with react-router-dom . Thus, I assume you would like to pass a variable between <Routes> .

You can use URL Parameter or Query Parameter to pass the variable between routes.

URL Parameter example:
https://reacttraining.com/react-router/web/example/url-params

Query Parameter example:
https://reacttraining.com/react-router/web/example/query-parameters

I had wrote an example of URL Paramater for your reference:
https://codesandbox.io/s/react-query-param-example-1ol6u

Good luck.

Answer 2

You can do what @YingHua mentioned in answer and one more thing you can do is like below.

OnClick you can call one function and from that function you can redirect with data.

 this.props.history.push({
     pathname: '/somewhere',
      state: { fromDashboard: true }
    });