Question

I need to display some dates on windows phone with day and month only.

For example, January 1st, for American users I want the text to be ‘1/31′ and for UK users I want it to be ’31/1’.

What’s the easiest way to achieve something like this?

UPDATE:
My app will be available in a lot of countries. Do I have to specify each culture to get what I want?

For example,

de-DE Culture                         01.10
en-US Culture                         10/1
es-ES Culture                         01/10
fr-FR Culture                         01/10

The left column contains some countries my app will support, the right column is how I want my date text to be.

Is there any generic way I can achieve this?

Answer 1

Wow, that question is particularly interesting! I didn’t found some obvious solution, so here it goes:

    char[] trimmer = DateTimeFormatInfo.CurrentInfo.DateSeparator.ToCharArray();
    string dateStr = date.ToString("d").Replace(date.ToString("yyyy"), string.Empty).Trim(trimmer);

If you can’t use DateTimeFormatInfo, then following code should do the trick:

string tmp = date.ToString("d").Replace(date.ToString("yyyy"), string.Empty);
char last = tmp[tmp.Length - 1];
char[] trimmer = char.IsDigit(last) ? new char[] { tmp[0] } : new char[] { last };
string dateStr = tmp.Trim(trimmer);

As @ken2k correctly mentioned, this solution is also flawed (and much more than I actually expected). Here is the complere test suite (compile as console application):

using System;
using System.Diagnostics;
using System.Globalization;

class Program
{
    static void Main(string[] args)
    {
        CultureInfo[] cultures = CultureInfo.GetCultures(CultureTypes.SpecificCultures);

        DateTime date = DateTime.Now;

        foreach (CultureInfo culture in cultures)
        {
            string tmp = date.ToString("d", culture).Replace(date.ToString("yyyy", culture), string.Empty);
            char last = tmp[tmp.Length - 1];
            char[] trimmer = char.IsDigit(last) ? new char[] { tmp[0] } : new char[] { last };
            string dateStr = tmp.Trim(trimmer);

            Console.WriteLine(string.Format("{0,12}, {1,15} => {2,10}", culture.IetfLanguageTag, date.ToString("d", culture), dateStr));
        }

        if (Debugger.IsAttached)
        {
            Console.WriteLine();
            Console.WriteLine("Press any key to exit..");
            Console.ReadKey();
        }
    }
}

Further optimization is possible (at least in full framework), however it’s becoming rather complex (limited framework of a Windows Phone adds complexity also) and it’s not clear if such date representation will make sense in some cultures. For example in some cultures date part separator is a two-char sequence:

hu-HU, 2012. 08. 14. => 08. 14

does 08. 14 actually look good? Or should it be 08. 14.? I’m not sure. If I were you, and I really want to handle maximum amount of cultures, I would just stick with standard “d” format specifier.