Set day and month format, but not their order

Question

I know about Datetime formats. "dd" stands for day from 01 to 31, "MM" - the month from 01 through 12. I need this format. But if I write "dd MM"(in my case in ToString() method) it will always put day before the month. How can I set this format(dd and MM) without changing the order(what comes first - day or month) from current locale? So if in current culture day comes first I want to receive "20 08 2012"(separator doesn't matter here), and if month comes first - "08 20 2012"

Answer 1

You can use the MonthDayPattern from the current locale to get the relative order of the two items, and then construct either dd MM or MM dd:

var mdp = CultureInfo.CurrentCulture.DateTimeFormat.MonthDayPattern;
string pattern = mdp.IndexOf('M') < mdp.IndexOf('d') ? "MM dd" : "dd MM";

Answer 2

Have a look at the culture's MonthDayPattern. Maybe you can customize it to your needs, e.g.

string FormatWithMonthDayPattern(DateTime dateTime, CultureInfo cultureInfo)
{
    var pattern = cultureInfo.DateTimeFormat.MonthDayPattern;
    return dateTime.ToString(Regex.Replace(pattern, "M+", "MM"));
}

var result1 = FormatWithMonthDayPattern(DateTime.Now, new CultureInfo("en-US"));
// result1 == "08 20"

var result2 = FormatWithMonthDayPattern(DateTime.Now, new CultureInfo("fr-FR"));
// result2 == "20 08"