.net Culture specific 12/24 hour formatting

Question

Is there a way to keep the culture specific date time formatting but force 12/24 hour rendering? I know I can do a lot with the actual date/time format string like HH:mm:ss and hh:mm:ss but I would like to honor the current user culture formatting (i.e. mm/dd/yyyy or yyyy/mm/dd, etc), just force 12/24 hour time rendering.

Tocology

Answer 1

I'd probably do something like this:

        var culture = CultureInfo.CurrentCulture;
        var pattern = culture.DateTimeFormat.LongTimePattern; // or pick which one you want to use;
        var newPattern = pattern.Replace("h", "H").Replace("t", "");
        DateTime.Now.ToString(newPattern); // or use whatever DateTime you want to use

From the chat:

Here is a list of all cultures' long time pattern strings, and how they would be modified:

Old: hh:mm:ss tt New: HH:mm:ss 
Old: HH:mm:ss 'ч.' New: HH:mm:ss 'ч.'
Old: HH:mm:ss New: HH:mm:ss
Old: H:mm:ss New: H:mm:ss
Old: h:mm:ss tt New: H:mm:ss 
Old: tt h:mm:ss New:  H:mm:ss
Old: h:mm:ss.tt New: H:mm:ss.
Old: HH.mm.ss New: HH.mm.ss
Old: tt hh:mm:ss New:  HH:mm:ss

Kayekayla

+1: This may work. Curious to see how it reacts to manipulating the time format in some cultures. – Fortunio

I'm doing some testing now -- but I think this is what I was looking for. Ill accept the answer soon if this works. Thanks.... – Tocology

McKay, this looks like this is going to work for me. I appreciate the time reading what i wrote and actually thinking of a solution. The replace is a simple easy approach too. Ill mark this as the answer. – Tocology

Don't forget to add a Trim() after the replacements to avoid those leading and trailing spaces left behind after removing the "tt". – Duwe

Answer 2

You can use custom date/time format strings - e.g.:

For 12 hour rendering:

DateTime.Now.ToString("hh:mm:ss tt");

for 24-hour rendering:

DateTime.Now.ToString("HH:mm:ss");

To combine with a date format from the current culture, you can use one of:

DateTime.Now.ToString("d") + DateTime.Now.ToString(" hh:mm:ss tt");
DateTime.Now.ToString(CultureInfo.CurrentCulture.DateTimeFormat.ShortDatePattern + 
                                      " hh:mm:ss tt");

Oletta

He specifically stated he wanted to keep the current culture mostly. – Kayekayla

Answer 3

That depends on what cultures you're talking about. Some cultures don't accept 24 hour time, and others don't accept AM/PM. The safest choice is probably InvariantCulture.

Fortunio

He specifically stated he wanted to observe the current culture except for 24 hour strings. – Kayekayla

He said he wanted to force 12/24 hour rendering, but honor the culture... not sure what you mean. – Fortunio

The way I understood it, he wants to use a date format that is native to the culture, but format the time in hh or HH format, which may or may not work depending on the culture. – Fortunio

He said he wanted to keep everything the same about the current culture (slashes, order of month / day / year), but force 24 hour rendering. As in, he wants to violate only one rule of the current culture (12/24 hr). Otherwise keep everything the same. – Kayekayla

See my answer to understand what I think he means. – Kayekayla

Yes, but depending on what culture is selected that may not be possible. I wish Jon Skeet were here, because he could give examples of which countries this would cause problems for. – Fortunio

let us continue this discussion in chat – Kayekayla

Answer 4

Use DateTime.ToShortTimeString() to ensure you get the version that is correct for your culture. Note: It does use the current culture settings of the thread by default.

Sample (from MSDN):

// This code example demonstrates the DateTime.ToLongDateString(),
// DateTime.ToLongTimeString(), DateTime.ToShortDateString(), and
// DateTime.ToShortTimeString() methods.

using System;
using System.Threading;
using System.Globalization;

class Sample 
{
    public static void Main() 
    {
    string msg1 = "The date and time patterns are defined in the DateTimeFormatInfo \n" +
                  "object associated with the current thread culture.\n";

// Initialize a DateTime object.
    Console.WriteLine("Initialize the DateTime object to May 16, 2001 3:02:15 AM.\n");
    DateTime myDateTime = new System.DateTime(2001, 5, 16, 3, 2, 15);

// Identify the source of the date and time patterns.
    Console.WriteLine(msg1);

// Display the name of the current culture.
    CultureInfo ci = Thread.CurrentThread.CurrentCulture;
    Console.WriteLine("Current culture: \"{0}\"\n", ci.Name);

// Display the long date pattern and string.
    Console.WriteLine("Long date pattern: \"{0}\"", ci.DateTimeFormat.LongDatePattern);
    Console.WriteLine("Long date string:  \"{0}\"\n", myDateTime.ToLongDateString());

// Display the long time pattern and string.
    Console.WriteLine("Long time pattern: \"{0}\"", ci.DateTimeFormat.LongTimePattern);
    Console.WriteLine("Long time string:  \"{0}\"\n", myDateTime.ToLongTimeString());

// Display the short date pattern and string.
    Console.WriteLine("Short date pattern: \"{0}\"", ci.DateTimeFormat.ShortDatePattern);
    Console.WriteLine("Short date string:  \"{0}\"\n", myDateTime.ToShortDateString());

// Display the short time pattern and string.
    Console.WriteLine("Short time pattern: \"{0}\"", ci.DateTimeFormat.ShortTimePattern);
    Console.WriteLine("Short time string:  \"{0}\"\n", myDateTime.ToShortTimeString());
    }
}

/*
This code example produces the following results:

Initialize the DateTime object to May 16, 2001 3:02:15 AM

The date and time patterns are defined in the DateTimeFormatInfo
object associated with the current thread culture.

Current culture: "en-US"

Long date pattern: "dddd, MMMM dd, yyyy"
Long date string:  "Wednesday, May 16, 2001"

Long time pattern: "h:mm:ss tt"
Long time string:  "3:02:15 AM"

Short date pattern: "M/d/yyyy"
Short date string:  "5/16/2001"

Short time pattern: "h:mm tt"
Short time string:  "3:02 AM"

*/

Michale

He specifically stated he wanted to change the current culture a little. – Kayekayla

@Kayekayla It sounded to me like he just wanted to render it in 12/24 based on the user's culture, but the MSDN snippet and your answer show how to obtain the base pattern for manipulation. – Michale

so how does: DateTime.ToShortTimeString() "render it in 12/24 based on the user's culture"? – Kayekayla

@Kayekayla He would adjust the culture for the thread to the user's culture prior to calling the method... Not sure I understand your question. – Michale

Precisely, I think that was his question? – Kayekayla