Find time zone and time from given string of timestamp

You can get a DateTimeOffset which contains both the local time and the offset from UTC, using DateTimeOffset.ParseExact. However, there may be multiple time zones observing the same offset from UTC at that time, so you can't get the actual time zone.

Sample code:

using System;
using System.Globalization;

class Test
{
    static void Main()        
    {
        string text = "2013-09-17T14:55:00.355-08:00";
        DateTimeOffset dto = DateTimeOffset.ParseExact(text,
            "yyyy-MM-dd'T'HH:mm:ss.fffzzz",
            CultureInfo.InvariantCulture);
        Console.WriteLine(dto);
    }
} 

Or using my Noda Time library:

using System;
using NodaTime;
using NodaTime.Text;

class Test
{
    static void Main()        
    {
        string text = "2013-09-17T14:55:00.355-08:00";
        // Use GeneralIsoPattern just to get a default culture/template value
        OffsetDateTime odt = OffsetDateTimePattern.GeneralIsoPattern
            .WithPatternText("yyyy-MM-dd'T'HH:mm:ss.fffo<+HH:mm>")
            .Parse(text)
            .Value;
        Console.WriteLine(odt);
    }
}