解决HTTP请求中多词参数编码问题：JavaScript与PHP实践

// 获取国家坐标并在用户选择国家时设置地图视图
selectElement.change(function () {
    var selectedCountry = $(this).val();
    // 使用 encodeURIComponent() 编码参数值
    axios.get('../assets/php/getCountryByName.php?countryName=' + encodeURIComponent(selectedCountry))
        .then(function (response) {
            console.log(response.data.results[0]);
            console.log(response.data.message);
            var country = response.data.results[0].geometry;
            coordinatesToTravel = [country.lat, country.lng];

            console.log('Coordinates got from response: ', coordinatesToTravel);

            // 设置地图视图到所选国家
            map.setView(coordinatesToTravel, 5);
            getCountryByLocation(coordinatesToTravel[0], coordinatesToTravel[1])

        })
        .catch(function (error) {
            console.log(error);
        });
});

<?php

require_once __DIR__ . '/../../vendor/autoload.php';
$dotenv = Dotenv\Dotenv::createImmutable(__DIR__ . '/../../');
$dotenv->load();

$opencage = $_ENV['OPENCAGE_API_KEY'];


    ini_set('display_errors', 'On');
    error_reporting(E_ALL);

    $executionStartTime = microtime(true);

    // 对 $_REQUEST['countryName'] 的值进行 urlencode 编码
    // 对 API Key 也进行 urlencode 编码，尽管通常不需要，但作为参数值编码是最佳实践
    $encodedCountryName = urlencode($_REQUEST['countryName']);
    $encodedOpencageKey = urlencode($opencage);

    $url='https://api.opencagedata.com/geocode/v1/json?q=' . $encodedCountryName . '&key=' . $encodedOpencageKey;

    $ch = curl_init();
    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($ch, CURLOPT_URL,$url);

    $result=curl_exec($ch);

    curl_close($ch);

    $decode = json_decode($result,true);

    $output = $decode;
    $output['status']['code'] = "200";
    $output['status']['name'] = "ok";
    $output['status']['description'] = "success";
    $output['status']['returnedIn'] = intval((microtime(true) - $executionStartTime) * 1000) . " ms";
    $output['message'] = '$_REQUEST["countryName"] value got on php module: ' . $_REQUEST['countryName'];

    header('Content-Type: application/json; charset=UTF-8');

    echo json_encode($output); 
?>