C# 同步更新系统时间

前言

在定位用户问题时，发现有些电脑，会出现系统时间不是最新的问题。

可能原因：

1. 取消了勾选服务器时间同步
2. 当前安装的系统，是一个未知来源系统，导致系统时间更新失败

而系统时间不正确，会导致IE选项-证书，校验不通过~

更新系统时间

1. 连接时间服务器

时间服务器列表（推荐）： string[] timeHosts = { "time.windows.com", "time.nist.gov" };

    /// <summary>
    /// 连接时间服务器
    /// </summary>
    /// <param name="socket">服务器接口</param>
    /// <param name="startTime">开始时间</param>
    /// <param name="errorMsg">错误信息</param>
    /// <returns></returns>
    private static bool TryConnectToTimeServer(out Socket socket, out DateTime startTime, out string errorMsg)
    {
        socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);//创建Socket   
        socket.ReceiveTimeout = 10 * 1000;//设置超时时间   
        errorMsg = string.Empty;
        startTime = DateTime.Now;

        // 遍历时间服务器列表   
        foreach (string strHost in timeHosts)
        {
            try
            {
                // 记录开始的时间   
                startTime = DateTime.Now;

                var iphostinfo = Dns.GetHostEntry(strHost);
                var ip = iphostinfo.AddressList[0];
                //建立IPAddress对象与端口，创建IPEndPoint节点:   
                int port = 13;
                var ipe = new IPEndPoint(ip, port);
                //连接到服务器   
                socket.Connect(ipe);
                // 如果连接到服务器就跳出  
                if (socket.Connected) break;
            }
            catch (Exception ex)
            {
                errorMsg = $"时间服务器连接失败！
错误信息：{ex.Message}系统提示";
            }
        }
        return socket.Connected;
    }

2. 从服务器接收数据

    /// <summary>
    /// 从服务器接收数据
    /// </summary>
    /// <param name="socket"></param>
    /// <returns></returns>
    private static StringBuilder ReceiveMessageFromServer(Socket socket)
    {
        //SOCKET同步接受数据   
        byte[] receiveBytes = new byte[1024];
        int nBytes, nTotalBytes = 0;
        StringBuilder sb = new StringBuilder();
        System.Text.Encoding encoding = Encoding.UTF8;

        while ((nBytes = socket.Receive(receiveBytes, 0, 1024, SocketFlags.None)) > 0)
        {
            nTotalBytes += nBytes;
            sb.Append(encoding.GetString(receiveBytes, 0, nBytes));
        }

        return sb;
    }

3. 更新本地时间

    /// <summary>
    /// 更新系统时间
    /// </summary>
    /// <returns>更新结果</returns>
    public static string UpdateSystemTime()
    {
        try
        {
            var connected = TryConnectToTimeServer(out Socket socket, out var startTime, out string errorMsg);
            if (connected)
            {
                var receivedMsg = ReceiveMessageFromServer(socket);
                socket.Close();
                //切割字符串 
                string[] receiveMsgList = receivedMsg.ToString().Split(' ');
                if (receiveMsgList.Length >= 3)
                {
                    var dateTimeValue = receiveMsgList[1] + " " + receiveMsgList[2];
                    SetLocalTime(startTime, dateTimeValue);
                }
            }
            else
            {
                return errorMsg;
            }
        }
        catch (Exception e)
        {
            return $"函数{nameof(UpdateSystemTime)}执行异常，{e.Message}";
        }
        return "时间已同步";
    }
    /// <summary>
    /// 设置系统时间
    /// </summary>
    /// <param name="startTime">请求服务器时的开始时间</param>
    /// <param name="dateTimeValue">服务器返回的时间</param>
    private static void SetLocalTime(DateTime startTime, string dateTimeValue)
    {
        // 得到开始到现在所消耗的时间 
        TimeSpan k = DateTime.Now - startTime;
        // 减去中途消耗的时间
        DateTime updatedUtcTime = Convert.ToDateTime(dateTimeValue).Subtract(-k);

        //处置北京时间 +8时   
        var updatedTime = updatedUtcTime.AddHours(8);

        //转换System.DateTime到SystemTime   
        SystemTime systemTime = new SystemTime();
        systemTime.FromDateTime(updatedTime);

        //调用Win32 API设置系统时间   
        Win32API.SetLocalTime(ref systemTime);
    }

系统时间辅助类 & Win32API ：

    /// <summary>
    /// 系统时间帮助类
    /// </summary>
    public struct SystemTime
    {
        public ushort wYear;
        public ushort wMonth;
        public ushort wDayOfWeek;
        public ushort wDay;
        public ushort wHour;
        public ushort wMinute;
        public ushort wSecond;
        public ushort wMilliseconds;

        /// <summary>
        /// 从System.DateTime转换。
        /// </summary>
        /// <param name="time">System.DateTime类型的时间。</param>
        public void FromDateTime(DateTime time)
        {
            wYear = (ushort)time.Year;
            wMonth = (ushort)time.Month;
            wDayOfWeek = (ushort)time.DayOfWeek;
            wDay = (ushort)time.Day;
            wHour = (ushort)time.Hour;
            wMinute = (ushort)time.Minute;
            wSecond = (ushort)time.Second;
            wMilliseconds = (ushort)time.Millisecond;
        }
        /// <summary>
        /// 转换为System.DateTime类型。
        /// </summary>
        /// <returns></returns>
        public DateTime ToDateTime()
        {
            return new DateTime(wYear, wMonth, wDay, wHour, wMinute, wSecond, wMilliseconds);
        }
        /// <summary>
        /// 静态方法。转换为System.DateTime类型。
        /// </summary>
        /// <param name="time">SYSTEMTIME类型的时间。</param>
        /// <returns></returns>
        public static DateTime ToDateTime(SystemTime time)
        {
            return time.ToDateTime();
        }
    }

    /// <summary>
    /// 系统更新时间DLL
    /// </summary>
    public class Win32API
    {
        [DllImport("Kernel32.dll")]
        public static extern bool SetLocalTime(ref SystemTime Time);
        [DllImport("Kernel32.dll")]
        public static extern void GetLocalTime(ref SystemTime Time);
    }

Github地址：IE环境修复工具