System.TimeZone.ToUniversalTime C# (CSharp) Méthode

        public virtual DateTime ToUniversalTime(DateTime time) {
            if (time.Kind == DateTimeKind.Utc) {
                return time;
            }
            long tickCount = time.Ticks - GetUtcOffset(time).Ticks;
            if (tickCount>DateTime.MaxTicks) {
                return new DateTime(DateTime.MaxTicks, DateTimeKind.Utc);
            }
            if (tickCount<DateTime.MinTicks) {
                return new DateTime(DateTime.MinTicks, DateTimeKind.Utc);
            }
            return new DateTime(tickCount, DateTimeKind.Utc);
        }

    public static double GetSystemDateTimeSec_ByNow(System.DateTime _SpecifiedTime)
    {
        System.DateTime timeStampUTC = m_LocalTimeZone.ToUniversalTime(_SpecifiedTime);
        System.TimeSpan timeSpan     = (timeStampUTC - System.DateTime.Now);
        double          ret          = timeSpan.TotalSeconds;

        return(ret);
    }