c# 获取北京时间更新本地计算机

     class UpdateDateTime
     {
        [DllImport("Kernel32.dll")]
        private static extern void SetLocalTime([In, Out]   SystemTime st); 

        public static void UpdateTime()
        {
            Uri uri = new Uri("http://www.beijing-time.org/time15.asp");
            WebRequest request = WebRequest.Create(uri);
            WebResponse response = request.GetResponse();
            StreamReader reader = new StreamReader(response.GetResponseStream(), Encoding.GetEncoding("gbk"));

            string html = reader.ReadToEnd();
            reader.Close();
            reader.Dispose();
            response.Close();

            if (html[html.Length-].Equals(';'))
            {
                html = html.Remove(html.Length - );
            }

            string[] arr = html.Split(';');
            SystemTime st = new SystemTime();

            foreach (string str in arr)
            {
                switch (str.Split('=')[].Trim().ToLower())
                {
                    case "nyear":
                        st.Year = Convert.ToInt16(str.Split('=')[]);
                        break;
                    case "nmonth":
                        st.Month = Convert.ToInt16(str.Split('=')[]);
                        break;
                    case "nday":
                        st.Day = Convert.ToInt16(str.Split('=')[]);
                        break;
                    case "nhrs":
                        st.Hour = Convert.ToInt16(str.Split('=')[]);
                        break;
                    case "nmin":
                        st.Minute = Convert.ToInt16(str.Split('=')[]);
                        break;
                    case "nsec":
                        st.Second = Convert.ToInt16(str.Split('=')[]);
                        break;
                }
            }
            SetLocalTime(st);
        }
    }

    [StructLayout(LayoutKind.Sequential)]
    class SystemTime
    {
        ///
        ///系统时间类
        ///
        public short Year;
        public short Month;
        public short DayOfWeek;
        public short Day;
        public short Hour;
        public short Minute;
        public short Second;
        public short Milliseconds;
    }