Telegram-机器人命令问题(php)

<?php
$botToken = 'YOUR_BOT_TOKEN';
$apiUrl = "https://api.telegram.org/bot$botToken";

// 处理接收到的消息
function handleMessage($update) {
    $chatId = $update->message->chat->id;
    $text = $update->message->text;

    if ($text == '/start') {
        sendMessage($chatId, 'Hello! How can I help you?');
    }
}

// 发送消息
function sendMessage($chatId, $text) {
    global $apiUrl;
    $url = "$apiUrl/sendMessage?chat_id=$chatId&text=$text";
    file_get_contents($url);
}

// 获取更新
function getUpdates() {
    global $apiUrl;
    $url = "$apiUrl/getUpdates";
    $response = file_get_contents($url);
    return json_decode($response);
}

while (true) {
    $updates = getUpdates();
    foreach ($updates->result as $update) {
        handleMessage($update);
    }
    sleep(1);
}
?>