php获取网络北京时间

<?php
function getBeijingTime() {
    // 北京时间的NTP服务器地址
    $ntpServer = 'time.asia.apple.com';
    $port = 123;
    $timeout = 1;

    // 创建UDP套接字
    $socket = socket_create(AF_INET, SOCK_DGRAM, SOL_UDP);
    if (!$socket) {
        die('Socket creation failed: ' . socket_strerror(socket_last_error()));
    }

    // 设置超时
    socket_set_option($socket, SOL_SOCKET, SO_RCVTIMEO, array('sec' => $timeout, 'usec' => 0));

    // 发送NTP请求
    $ntpRequest = "\x1b" . str_repeat("\0", 47);
    socket_sendto($socket, $ntpRequest, strlen($ntpRequest), 0, $ntpServer, $port);

    // 接收NTP响应
    $response = '';
    $bytesReceived = socket_recvfrom($socket, $response, 48, 0, $ntpServer, $port);
    if ($bytesReceived === false) {
        die('Socket receive failed: ' . socket_strerror(socket_last_error()));
    }

    // 解析NTP响应
    $ntpResponse = unpack('N12', $response);
    $secondsSinceEpoch = $ntpResponse[11] + ($ntpResponse[12] * 256);
    $fraction = ($ntpResponse[13] + ($ntpResponse[14] * 256) + ($ntpResponse[15] * 65536)) / 4294967296;

    // 计算时间戳
    $timestamp = $secondsSinceEpoch - 2208988800; // 1970-01-01 00:00:00 UTC to 1900-01-01 00:00:00 UTC
    $date = new DateTime("@$timestamp");
    $date->setTimezone(new DateTimeZone('Asia/Shanghai'));

    // 关闭套接字
    socket_close($socket);

    return $date->format('Y-m-d H:i:s');
}

echo getBeijingTime();
?>