I\'m playing with some C# code to try to gain an understanding of how subtracting DateTime objects in C# works with respect to Daylight Saving Time.
Per Google and o
Ok, so I made some minor changes to your code. Not sure if this is what you are trying to achieve or not but this will give you what you want...
static void Main() {
TimeZoneInfo easternStandardTime = TimeZoneInfo.FindSystemTimeZoneById("Eastern Standard Time");
TimeZone timeZone = TimeZone.CurrentTimeZone;
DateTime oneAm = TimeZoneInfo.ConvertTime(new DateTime(2017, 03, 12, 01, 00, 00), easternStandardTime);
DateTime fourAm = TimeZoneInfo.ConvertTime(new DateTime(2017, 03, 12, 04, 00, 00), easternStandardTime);
DaylightTime time = timeZone.GetDaylightChanges(fourAm.Year);
TimeSpan difference = ((fourAm - time.Delta) - oneAm);
Console.WriteLine(oneAm);
Console.WriteLine(fourAm);
Console.WriteLine(TimeZoneInfo.Local.IsDaylightSavingTime(oneAm));
Console.WriteLine(TimeZoneInfo.Local.IsDaylightSavingTime(fourAm));
Console.WriteLine(difference);
Console.ReadLine();
}