Well, with a lead in like that I could not help but post.  This sample comes from a friend of mine working who is helping me with a little book project...

using System;

using System.Globalization;

 

namespace Samples

{

  public class DateTimeFormatInfoSample

  {

    public static void Main()

    {

      DateTime d = DateTime.Now;

      DateTimeFormatInfo i =

          new CultureInfo("fr-FR").DateTimeFormat;

      string[] f =

           i.GetAllDateTimePatterns();

      foreach(string s in f)

        Console.WriteLine("ToString(\"{0}\") yields: {1}",

                          s, d.ToString(s, i));

      i = new CultureInfo("en-AU").DateTimeFormat;

      f = i.GetAllDateTimePatterns();

      foreach(string s in f)

        Console.WriteLine("ToString(\"{0}\") yields: {1}",

                          s, d.ToString(s, i));

 

    }

  }

}

And of course, here is the output for your reference:

ToString("dd/MM/yyyy") yields: 21/04/2003
ToString("dd/MM/yy") yields: 21/04/03
ToString("dd.MM.yy") yields: 21.04.03
ToString("dd-MM-yy") yields: 21-04-03
ToString("yyyy-MM-dd") yields: 2003-04-21
ToString("dddd d MMMM yyyy") yields: lundi 21 avril 2003
ToString("d MMM yy") yields: 21 avr. 03
ToString("d MMMM yyyy") yields: 21 avril 2003
ToString("dddd d MMMM yyyy HH:mm") yields: lundi 21 avril 2003 22:15
ToString("dddd d MMMM yyyy H:mm") yields: lundi 21 avril 2003 22:15
ToString("dddd d MMMM yyyy HH.mm") yields: lundi 21 avril 2003 22.15
ToString("dddd d MMMM yyyy HH' h 'mm") yields: lundi 21 avril 2003 22 h 15
ToString("d MMM yy HH:mm") yields: 21 avr. 03 22:15
ToString("d MMM yy H:mm") yields: 21 avr. 03 22:15
ToString("d MMM yy HH.mm") yields: 21 avr. 03 22.15
ToString("d MMM yy HH' h 'mm") yields: 21 avr. 03 22 h 15
ToString("d MMMM yyyy HH:mm") yields: 21 avril 2003 22:15
ToString("d MMMM yyyy H:mm") yields: 21 avril 2003 22:15
ToString("d MMMM yyyy HH.mm") yields: 21 avril 2003 22.15
ToString("d MMMM yyyy HH' h 'mm") yields: 21 avril 2003 22 h 15
ToString("dddd d MMMM yyyy HH:mm:ss") yields: lundi 21 avril 2003 22:15:16
ToString("dddd d MMMM yyyy H:mm:ss") yields: lundi 21 avril 2003 22:15:16
ToString("dddd d MMMM yyyy HH.mm") yields: lundi 21 avril 2003 22.15
ToString("dddd d MMMM yyyy HH' h 'mm") yields: lundi 21 avril 2003 22 h 15
ToString("d MMM yy HH:mm:ss") yields: 21 avr. 03 22:15:16
ToString("d MMM yy H:mm:ss") yields: 21 avr. 03 22:15:16
ToString("d MMM yy HH.mm") yields: 21 avr. 03 22.15
ToString("d MMM yy HH' h 'mm") yields: 21 avr. 03 22 h 15
ToString("d MMMM yyyy HH:mm:ss") yields: 21 avril 2003 22:15:16
ToString("d MMMM yyyy H:mm:ss") yields: 21 avril 2003 22:15:16
ToString("d MMMM yyyy HH.mm") yields: 21 avril 2003 22.15
ToString("d MMMM yyyy HH' h 'mm") yields: 21 avril 2003 22 h 15
ToString("dd/MM/yyyy HH:mm") yields: 21/04/2003 22:15
ToString("dd/MM/yyyy H:mm") yields: 21/04/2003 22:15
ToString("dd/MM/yyyy HH.mm") yields: 21/04/2003 22.15
ToString("dd/MM/yyyy HH' h 'mm") yields: 21/04/2003 22 h 15
ToString("dd/MM/yy HH:mm") yields: 21/04/03 22:15
ToString("dd/MM/yy H:mm") yields: 21/04/03 22:15
ToString("dd/MM/yy HH.mm") yields: 21/04/03 22.15
ToString("dd/MM/yy HH' h 'mm") yields: 21/04/03 22 h 15
ToString("dd.MM.yy HH:mm") yields: 21.04.03 22:15
ToString("dd.MM.yy H:mm") yields: 21.04.03 22:15
ToString("dd.MM.yy HH.mm") yields: 21.04.03 22.15
ToString("dd.MM.yy HH' h 'mm") yields: 21.04.03 22 h 15
ToString("dd-MM-yy HH:mm") yields: 21-04-03 22:15
ToString("dd-MM-yy H:mm") yields: 21-04-03 22:15
ToString("dd-MM-yy HH.mm") yields: 21-04-03 22.15
ToString("dd-MM-yy HH' h 'mm") yields: 21-04-03 22 h 15
ToString("yyyy-MM-dd HH:mm") yields: 2003-04-21 22:15
ToString("yyyy-MM-dd H:mm") yields: 2003-04-21 22:15
ToString("yyyy-MM-dd HH.mm") yields: 2003-04-21 22.15
ToString("yyyy-MM-dd HH' h 'mm") yields: 2003-04-21 22 h 15
ToString("dd/MM/yyyy HH:mm:ss") yields: 21/04/2003 22:15:16
ToString("dd/MM/yyyy H:mm:ss") yields: 21/04/2003 22:15:16
ToString("dd/MM/yyyy HH.mm") yields: 21/04/2003 22.15
ToString("dd/MM/yyyy HH' h 'mm") yields: 21/04/2003 22 h 15
ToString("dd/MM/yy HH:mm:ss") yields: 21/04/03 22:15:16
ToString("dd/MM/yy H:mm:ss") yields: 21/04/03 22:15:16
ToString("dd/MM/yy HH.mm") yields: 21/04/03 22.15
ToString("dd/MM/yy HH' h 'mm") yields: 21/04/03 22 h 15
ToString("dd.MM.yy HH:mm:ss") yields: 21.04.03 22:15:16
ToString("dd.MM.yy H:mm:ss") yields: 21.04.03 22:15:16
ToString("dd.MM.yy HH.mm") yields: 21.04.03 22.15
ToString("dd.MM.yy HH' h 'mm") yields: 21.04.03 22 h 15
ToString("dd-MM-yy HH:mm:ss") yields: 21-04-03 22:15:16
ToString("dd-MM-yy H:mm:ss") yields: 21-04-03 22:15:16
ToString("dd-MM-yy HH.mm") yields: 21-04-03 22.15
ToString("dd-MM-yy HH' h 'mm") yields: 21-04-03 22 h 15
ToString("yyyy-MM-dd HH:mm:ss") yields: 2003-04-21 22:15:16
ToString("yyyy-MM-dd H:mm:ss") yields: 2003-04-21 22:15:16
ToString("yyyy-MM-dd HH.mm") yields: 2003-04-21 22.15
ToString("yyyy-MM-dd HH' h 'mm") yields: 2003-04-21 22 h 15
ToString("d MMMM") yields: 21 avril
ToString("d MMMM") yields: 21 avril
ToString("ddd, dd MMM yyyy HH':'mm':'ss 'GMT'") yields: lun., 21 avr. 2003 22:15:16 GMT
ToString("ddd, dd MMM yyyy HH':'mm':'ss 'GMT'") yields: lun., 21 avr. 2003 22:15:16 GMT
ToString("yyyy'-'MM'-'dd'T'HH':'mm':'ss") yields: 2003-04-21T22:15:16
ToString("HH:mm") yields: 22:15
ToString("H:mm") yields: 22:15
ToString("HH.mm") yields: 22.15
ToString("HH' h 'mm") yields: 22 h 15
ToString("HH:mm:ss") yields: 22:15:16
ToString("H:mm:ss") yields: 22:15:16
ToString("HH.mm") yields: 22.15
ToString("HH' h 'mm") yields: 22 h 15
ToString("yyyy'-'MM'-'dd HH':'mm':'ss'Z'") yields: 2003-04-21 22:15:16Z
ToString("dddd d MMMM yyyy HH:mm:ss") yields: lundi 21 avril 2003 22:15:16
ToString("dddd d MMMM yyyy H:mm:ss") yields: lundi 21 avril 2003 22:15:16
ToString("dddd d MMMM yyyy HH.mm") yields: lundi 21 avril 2003 22.15
ToString("dddd d MMMM yyyy HH' h 'mm") yields: lundi 21 avril 2003 22 h 15
ToString("d MMM yy HH:mm:ss") yields: 21 avr. 03 22:15:16
ToString("d MMM yy H:mm:ss") yields: 21 avr. 03 22:15:16
ToString("d MMM yy HH.mm") yields: 21 avr. 03 22.15
ToString("d MMM yy HH' h 'mm") yields: 21 avr. 03 22 h 15
ToString("d MMMM yyyy HH:mm:ss") yields: 21 avril 2003 22:15:16
ToString("d MMMM yyyy H:mm:ss") yields: 21 avril 2003 22:15:16
ToString("d MMMM yyyy HH.mm") yields: 21 avril 2003 22.15
ToString("d MMMM yyyy HH' h 'mm") yields: 21 avril 2003 22 h 15
ToString("MMMM yyyy") yields: avril 2003
ToString("MMMM yyyy") yields: avril 2003
ToString("d/MM/yyyy") yields: 21/04/2003
ToString("d/MM/yy") yields: 21/04/03
ToString("d/M/yy") yields: 21/4/03
ToString("d/M/yyyy") yields: 21/4/2003
ToString("dd/MM/yy") yields: 21/04/03
ToString("dd/MM/yyyy") yields: 21/04/2003
ToString("dd-MMM-yy") yields: 21-Apr-03
ToString("dd-MMMM-yyyy") yields: 21-April-2003
ToString("yyyy-MM-dd") yields: 2003-04-21
ToString("yy/MM/dd") yields: 03/04/21
ToString("yyyy/MM/dd") yields: 2003/04/21
ToString("dddd, d MMMM yyyy") yields: Monday, 21 April 2003
ToString("d MMMM yyyy") yields: 21 April 2003
ToString("dddd, d MMMM yyyy h:mm tt") yields: Monday, 21 April 2003 10:15 PM
ToString("dddd, d MMMM yyyy H:mm") yields: Monday, 21 April 2003 22:15
ToString("dddd, d MMMM yyyy HH:mm") yields: Monday, 21 April 2003 22:15
ToString("d MMMM yyyy h:mm tt") yields: 21 April 2003 10:15 PM
ToString("d MMMM yyyy H:mm") yields: 21 April 2003 22:15
ToString("d MMMM yyyy HH:mm") yields: 21 April 2003 22:15
ToString("dddd, d MMMM yyyy h:mm:ss tt") yields: Monday, 21 April 2003 10:15:16 PM
ToString("dddd, d MMMM yyyy H:mm:ss") yields: Monday, 21 April 2003 22:15:16
ToString("dddd, d MMMM yyyy HH:mm:ss") yields: Monday, 21 April 2003 22:15:16
ToString("d MMMM yyyy h:mm:ss tt") yields: 21 April 2003 10:15:16 PM
ToString("d MMMM yyyy H:mm:ss") yields: 21 April 2003 22:15:16
ToString("d MMMM yyyy HH:mm:ss") yields: 21 April 2003 22:15:16
ToString("d/MM/yyyy h:mm tt") yields: 21/04/2003 10:15 PM
ToString("d/MM/yyyy H:mm") yields: 21/04/2003 22:15
ToString("d/MM/yyyy HH:mm") yields: 21/04/2003 22:15
ToString("d/MM/yy h:mm tt") yields: 21/04/03 10:15 PM
ToString("d/MM/yy H:mm") yields: 21/04/03 22:15
ToString("d/MM/yy HH:mm") yields: 21/04/03 22:15
ToString("d/M/yy h:mm tt") yields: 21/4/03 10:15 PM
ToString("d/M/yy H:mm") yields: 21/4/03 22:15
ToString("d/M/yy HH:mm") yields: 21/4/03 22:15
ToString("d/M/yyyy h:mm tt") yields: 21/4/2003 10:15 PM
ToString("d/M/yyyy H:mm") yields: 21/4/2003 22:15
ToString("d/M/yyyy HH:mm") yields: 21/4/2003 22:15
ToString("dd/MM/yy h:mm tt") yields: 21/04/03 10:15 PM
ToString("dd/MM/yy H:mm") yields: 21/04/03 22:15
ToString("dd/MM/yy HH:mm") yields: 21/04/03 22:15
ToString("dd/MM/yyyy h:mm tt") yields: 21/04/2003 10:15 PM
ToString("dd/MM/yyyy H:mm") yields: 21/04/2003 22:15
ToString("dd/MM/yyyy HH:mm") yields: 21/04/2003 22:15
ToString("dd-MMM-yy h:mm tt") yields: 21-Apr-03 10:15 PM
ToString("dd-MMM-yy H:mm") yields: 21-Apr-03 22:15
ToString("dd-MMM-yy HH:mm") yields: 21-Apr-03 22:15
ToString("dd-MMMM-yyyy h:mm tt") yields: 21-April-2003 10:15 PM
ToString("dd-MMMM-yyyy H:mm") yields: 21-April-2003 22:15
ToString("dd-MMMM-yyyy HH:mm") yields: 21-April-2003 22:15
ToString("yyyy-MM-dd h:mm tt") yields: 2003-04-21 10:15 PM
ToString("yyyy-MM-dd H:mm") yields: 2003-04-21 22:15
ToString("yyyy-MM-dd HH:mm") yields: 2003-04-21 22:15
ToString("yy/MM/dd h:mm tt") yields: 03/04/21 10:15 PM
ToString("yy/MM/dd H:mm") yields: 03/04/21 22:15
ToString("yy/MM/dd HH:mm") yields: 03/04/21 22:15
ToString("yyyy/MM/dd h:mm tt") yields: 2003/04/21 10:15 PM
ToString("yyyy/MM/dd H:mm") yields: 2003/04/21 22:15
ToString("yyyy/MM/dd HH:mm") yields: 2003/04/21 22:15
ToString("d/MM/yyyy h:mm:ss tt") yields: 21/04/2003 10:15:16 PM
ToString("d/MM/yyyy H:mm:ss") yields: 21/04/2003 22:15:16
ToString("d/MM/yyyy HH:mm:ss") yields: 21/04/2003 22:15:16
ToString("d/MM/yy h:mm:ss tt") yields: 21/04/03 10:15:16 PM
ToString("d/MM/yy H:mm:ss") yields: 21/04/03 22:15:16
ToString("d/MM/yy HH:mm:ss") yields: 21/04/03 22:15:16
ToString("d/M/yy h:mm:ss tt") yields: 21/4/03 10:15:16 PM
ToString("d/M/yy H:mm:ss") yields: 21/4/03 22:15:16
ToString("d/M/yy HH:mm:ss") yields: 21/4/03 22:15:16
ToString("d/M/yyyy h:mm:ss tt") yields: 21/4/2003 10:15:16 PM
ToString("d/M/yyyy H:mm:ss") yields: 21/4/2003 22:15:16
ToString("d/M/yyyy HH:mm:ss") yields: 21/4/2003 22:15:16
ToString("dd/MM/yy h:mm:ss tt") yields: 21/04/03 10:15:16 PM
ToString("dd/MM/yy H:mm:ss") yields: 21/04/03 22:15:16
ToString("dd/MM/yy HH:mm:ss") yields: 21/04/03 22:15:16
ToString("dd/MM/yyyy h:mm:ss tt") yields: 21/04/2003 10:15:16 PM
ToString("dd/MM/yyyy H:mm:ss") yields: 21/04/2003 22:15:16
ToString("dd/MM/yyyy HH:mm:ss") yields: 21/04/2003 22:15:16
ToString("dd-MMM-yy h:mm:ss tt") yields: 21-Apr-03 10:15:16 PM
ToString("dd-MMM-yy H:mm:ss") yields: 21-Apr-03 22:15:16
ToString("dd-MMM-yy HH:mm:ss") yields: 21-Apr-03 22:15:16
ToString("dd-MMMM-yyyy h:mm:ss tt") yields: 21-April-2003 10:15:16 PM
ToString("dd-MMMM-yyyy H:mm:ss") yields: 21-April-2003 22:15:16
ToString("dd-MMMM-yyyy HH:mm:ss") yields: 21-April-2003 22:15:16
ToString("yyyy-MM-dd h:mm:ss tt") yields: 2003-04-21 10:15:16 PM
ToString("yyyy-MM-dd H:mm:ss") yields: 2003-04-21 22:15:16
ToString("yyyy-MM-dd HH:mm:ss") yields: 2003-04-21 22:15:16
ToString("yy/MM/dd h:mm:ss tt") yields: 03/04/21 10:15:16 PM
ToString("yy/MM/dd H:mm:ss") yields: 03/04/21 22:15:16
ToString("yy/MM/dd HH:mm:ss") yields: 03/04/21 22:15:16
ToString("yyyy/MM/dd h:mm:ss tt") yields: 2003/04/21 10:15:16 PM
ToString("yyyy/MM/dd H:mm:ss") yields: 2003/04/21 22:15:16
ToString("yyyy/MM/dd HH:mm:ss") yields: 2003/04/21 22:15:16
ToString("dd MMMM") yields: 21 April
ToString("dd MMMM") yields: 21 April
ToString("ddd, dd MMM yyyy HH':'mm':'ss 'GMT'") yields: Mon, 21 Apr 2003 22:15:16 GMT
ToString("ddd, dd MMM yyyy HH':'mm':'ss 'GMT'") yields: Mon, 21 Apr 2003 22:15:16 GMT
ToString("yyyy'-'MM'-'dd'T'HH':'mm':'ss") yields: 2003-04-21T22:15:16
ToString("h:mm tt") yields: 10:15 PM
ToString("H:mm") yields: 22:15
ToString("HH:mm") yields: 22:15
ToString("h:mm:ss tt") yields: 10:15:16 PM
ToString("H:mm:ss") yields: 22:15:16
ToString("HH:mm:ss") yields: 22:15:16
ToString("yyyy'-'MM'-'dd HH':'mm':'ss'Z'") yields: 2003-04-21 22:15:16Z
ToString("dddd, d MMMM yyyy h:mm:ss tt") yields: Monday, 21 April 2003 10:15:16PM
ToString("dddd, d MMMM yyyy H:mm:ss") yields: Monday, 21 April 2003 22:15:16
ToString("dddd, d MMMM yyyy HH:mm:ss") yields: Monday, 21 April 2003 22:15:16
ToString("d MMMM yyyy h:mm:ss tt") yields: 21 April 2003 10:15:16 PM
ToString("d MMMM yyyy H:mm:ss") yields: 21 April 2003 22:15:16
ToString("d MMMM yyyy HH:mm:ss") yields: 21 April 2003 22:15:16
ToString("MMMM yyyy") yields: April 2003
ToString("MMMM yyyy") yields: April 2003