您需要1.实现expresscors，2.从react向服务器添加代理
[1][https://expressjs.com/en/resources/middleware/cors.html](https://expressjs.com/en/resources/middleware/cors.html)

npm install cors

var express = require('express')
var cors = require('cors')

var app = express()

app.use(cors())

[2][https://create-react-app.dev/docs/proxying-api-requests-in-development/](https://create-react-app.dev/docs/proxying-api-requests-in-development/)
在您的react的package.json中，添加

"proxy": "http://localhost:5000",

请注意，这仅在开发中有效。
对于生产环境，您需要从服务器为客户端提供服务。

const express = require('express');
const cors = require('cors')
const path = require('path');

const app = express();

app.use(cors());

/**
 * add your API routes here to avoid them getting overtaken
 * by the statically served client
*/

/**
 * add this as the last handler
*/
if (process.env.NODE_ENV === "production") {
    const pathToClientBuild = path.join(__dirname, '..', 'path', 'to', 'client', 'build');
    app.use(express.static(pathToClientBuild));

    /**
     * experiment with '/' and '/*' and see what works best for you
    */
    app.get('/*', function (req, res) {
      res.sendFile(path.join(pathToClientBuild, 'index.html'));
    });
}

app.listen(5000);

(and要使其工作，您需要首先构建客户端，然后使用NODE_ENV=production node ./server.js服务服务器）。

const Login 9636634272 = () => {
  const options = {
    method: "GET",
    url: "http://localhost:5000/fblogin",
  };
  axios.request(options)
  .then((response)=>{
      console.log(response.data);
  })
  .catch((error)=>{
      console.error(error);
  });
};

const Login = () => {
  const options = {
    method: "GET",
    url: "http://localhost:5000/fblogin",
  };
  axios.request(options)
  .then((response)=>{
      console.log(response.data);
  })
  .catch((error)=>{
      console.error(error);
  });
};