C# Online Compiler | .NET Fiddle

<no name> by Anonymous

using System;
using System.Globalization;
					
public class Program
{
	public static void Main()
	{
		for (var i = 1; i <= 12; i++)
		{
			var date = new DateTime(2010, i, 1, 0, 0, 0);
			
			Console.WriteLine(date.ToString("MMM", new CultureInfo("nl-NL")));
		}
	}
}

 
using System;
using System.Globalization;
                    
public class Program
{
    public static void Main()
    {
        for (var i = 1; i <= 12; i++)
        {
            var date = new DateTime(2010, i, 1, 0, 0, 0);
            
            Console.WriteLine(date.ToString("MMM", new CultureInfo("nl-NL")));
        }
    }
}

Going from the bad format to DateTimeOffset w/TimeZone looks like:

    Formatted Date: 12:01am PT Jan-01 2001
    Date: 01/01/2001 00:01:00 -08:00
    TimeZone: (UTC-08:00) Pacific Time (Los Angeles)

    Formatted Date: 12:01am PT Jul-01 2001
    Date: 07/01/2001 00:01:00 -07:00
    TimeZone: (UTC-08:00) Pacific Time (Los Angeles)

    Formatted Date: 12:01am MT Jan-01 2001
    Date: 01/01/2001 00:01:00 -07:00
    TimeZone: (UTC-07:00) Mountain Time (Denver)

    Formatted Date: 12:01am MT Jul-01 2001
    Date: 07/01/2001 00:01:00 -06:00
    TimeZone: (UTC-07:00) Mountain Time (Denver)

Going the other way looks like

    UtcDate: 01/01/2021 07:00:00
    Zone:(UTC-07:00) Mountain Time (Phoenix)
    Date In Targe TimeZone: 01/01/2021 00:00:00 -07:00
    FormattedDate: 12:00am MT Jan-01 2021

    UtcDate: 07/01/2021 07:00:00
    Zone:(UTC-07:00) Mountain Time (Phoenix)
    Date In Targe TimeZone: 07/01/2021 00:00:00 -07:00
    FormattedDate: 12:00am PT Jul-01 2021

The full round trip looks like

    SourceDateTime: 12:01am PT Jan-01 2001
    ParsedDateTime: 01/01/2001 00:01:00 -08:00
    FormattedDateTime: 12:01am PT Jan-01 2001

    SourceDateTime: 12:01am PT Jul-01 2001
    ParsedDateTime: 07/01/2001 00:01:00 -07:00
    FormattedDateTime: 12:01am PT Jul-01 2001

Last Run:	4:21:36 pm
Compile:	0.016s
Execute:	0.11s
Memory:	12.33Mb
CPU:	0.126s

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