我正在使用 React 和 PHP，我需要它來做一些特定的事情。我正在使用 Axios 向我的 PHP 頁面發(fā)送請求，然后更改我的數(shù)據(jù)庫。我需要更新我的 MySQL 數(shù)據(jù)庫表，如果用戶關(guān)閉頁面或?yàn)g覽器，則將is_logged值從true更改為false 。執(zhí)行此操作的代碼在窗口的beforeunload事件中設(shè)置。但是，數(shù)據(jù)庫永遠(yuǎn)不會更新。我想要做的事情在 React 中是可能的嗎？這是我的 React 組件代碼：import React, { useState, useEffect } from 'react';import axios from 'axios';import Viewers from './Viewers';const Live = ({ match }) => {  window.addEventListener("beforeunload", () => {    axios.get('http://localhost/live-streaming-app/get_viewers.php?=' + token)      .then(response => console.log(response))  })  // Set token from url  const token = match.params.token  //Get the fullname and update logged_in to true  const [fullname, setFullname] = useState("")  useEffect(() => {    axios.get('http://localhost/live-streaming-app/get_user.php?token=' + token)      .then(response => {        setFullname(response.data.fullname)        console.log("Data", response.data)      })      .catch(error => console.log(error))    return () => {      axios.get('http://localhost/live-streaming-app/get_viewers.php?=' + token)        .then(response => console.log(response))        .catch(error => console.log(error))    }  }, [token])  //Jsx for when user is unauthorised  const rejected = (    <div className="container text-center pt-5">      <h1>Rejected Connection</h1>      <p>You are unauthorised to view this page</p>    </div>  )  let my_render = ""  if (fullname && fullname != null) {    my_render = <Viewers fullname={fullname} />  } else {    my_render = rejected  }  return my_render};export default Live;這是名為的 PHP 頁面：<?phprequire 'connect.php';$token = $_GET['token'];$sql = "UPDATE `viewers` SET `logged_in`='false' WHERE `live_token`='{$token}'";if(mysqli_query($con, $sql)){  http_response_code(201);}else {  http_response_code(422);}exit;