在Unity中如何使用代码获取服务器上标准的背景时间

要获取服务器上的标准时间，您需要使用网络时间协议(NTP)与时间服务器进行通信。在Unity中，您可以使用NTPClient类从时间服务器获取时间。

以下是一个示例代码片段，演示如何使用NTPClient类获取时间：

using System;
using System.Net;
using System.Net.Sockets;

public class TimeManager : MonoBehaviour
{
    public static DateTime GetNetworkTime()
    {
        // Time server address
        const string ntpServer = "pool.ntp.org";

        // NTP message size - 16 bytes of the digest (RFC 2030)
        var ntpData = new byte[48];

        // Setting the Leap Indicator, Version Number and Mode values
        ntpData[0] = 0x1B; 

        // Connect to the time server
        var addresses = Dns.GetHostEntry(ntpServer).AddressList;
        var ipEndPoint = new IPEndPoint(addresses[0], 123);
        var socket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);

        socket.Connect(ipEndPoint);

        // Send the NTP request
        socket.Send(ntpData);

        // Receive the NTP response
        socket.Receive(ntpData);

        // Closing the socket
        socket.Close();

        // Offset to get to the "Transmit Timestamp" field (time at which the reply 
        // departed the server for the client, in 64-bit timestamp format."
        const byte serverReplyTime = 40;

        // Get the seconds part
        ulong intPart = BitConverter.ToUInt32(ntpData, serverReplyTime);

        // Get the seconds fraction
        ulong fractPart = BitConverter.ToUInt32(ntpData, serverReplyTime + 4);

        // Convert From big-endian to little-endian
        intPart = SwapEndianness(intPart);
        fractPart = SwapEndianness(fractPart);

        var milliseconds = (intPart * 1000) + ((fractPart * 1000) / 0x100000000L);

        // Convert the NTP time to DateTime (1900 -> 1970)
        var networkDateTime = new DateTime(1900, 1, 1, 0, 0, 0, DateTimeKind.Utc).AddMilliseconds((long)milliseconds).ToLocalTime();

        return networkDateTime;
    }

    private static uint SwapEndianness(ulong x)
    {
        return (uint)(((x & 0x000000ff) << 24) +
                       ((x & 0x0000ff00) << 8) +
                       ((x & 0x00ff0000) >> 8) +
                       ((x & 0xff000000) >> 24));
    }
}

您可以在需要获取服务器时间的脚本中调用GetNetworkTime()函数，它将返回当前时间的DateTime对象。请注意，此函数需要Internet连接才能与时间服务器通信。