Grey zone of DST

Question

does anybody knows how to handle grey zones of DST (when time doesn't exist): e.g.:

DateTime dt = new DateTime(2014,3,30,2,30,0);
TimeZoneInfo tziSV = TimeZoneInfo.FindSystemTimeZoneById("W. Europe Standard Time");
DateTime dtSV =TimeZoneInfo.ConvertTimeToUtc(dt,tziSV);

gives an error,when

DateTime dt = new DateTime(2014,3,30,2,30,0);
dt = dt.ToUniversalTime();
dt = TimeZoneInfo.ConvertTimeFromUtc(dt,tziSV);

gives 1:30 and then 3:30.

Thanks

Answer 1

I found a way of handling this grey zones by .net facilities

    DateTime dt = new DateTime(2014,3,30,2,30,0);
    TimeZoneInfo tziSV = TimeZoneInfo.FindSystemTimeZoneById("W. Europe Standard Time");

    if (tziSV.IsInvalidTime(dt))
    {
       dt = dt.Add(tziSV.GetUtcOffset(dt));
    }
    DateTime dtSV = TimeZoneInfo.ConvertTimeToUtc(dt,tziSV);