In the Locale part of DatePicker, instead of accepting a string, a variable of culture type

[capdiem]

Culture is a name but in some cases it needs changes. Currently, by filling the culture name in the Locale attribute, the default month and day names provided by the infrastructure are displayed, but they need customization. For example, the following code sample:

DateTime? date = new DateTime(2021, 02, 14); // 1399-11-26 in Persian calendar

    public CultureInfo GetPersianCulture()
    {
        var culture = new CultureInfo("fa-IR");
        DateTimeFormatInfo formatInfo = culture.DateTimeFormat;
        formatInfo.AbbreviatedDayNames = new[] { "ی", "د", "س", "چ", "پ", "ج", "ش" };
        formatInfo.DayNames = new[] { "یکشنبه", "دوشنبه", "سه شنبه", "چهار شنبه", "پنجشنبه", "جمعه", "شنبه" };
        var monthNames = new[]
        {
            "فروردین", "اردیبهشت", "خرداد", "تیر", "مرداد", "شهریور", "مهر", "آبان", "آذر", "دی", "بهمن",
            "اسفند",
            "",
        };
        formatInfo.AbbreviatedMonthNames =
            formatInfo.MonthNames =
                formatInfo.MonthGenitiveNames = formatInfo.AbbreviatedMonthGenitiveNames = monthNames;
        formatInfo.AMDesignator = "ق.ظ";
        formatInfo.PMDesignator = "ب.ظ";
        formatInfo.ShortDatePattern = "yyyy/MM/dd";
        formatInfo.LongDatePattern = "dddd, dd MMMM,yyyy";
        formatInfo.FirstDayOfWeek = DayOfWeek.Saturday;
        System.Globalization.Calendar cal = new PersianCalendar();
        FieldInfo fieldInfo = culture.GetType().GetField("calendar", BindingFlags.NonPublic | BindingFlags.Instance);
        if (fieldInfo != null)
            fieldInfo.SetValue(culture, cal);
        FieldInfo info = formatInfo.GetType().GetField("calendar", BindingFlags.NonPublic | BindingFlags.Instance);
        if (info != null)
            info.SetValue(formatInfo, cal);
        culture.NumberFormat.NumberDecimalSeparator = "/";
        culture.NumberFormat.DigitSubstitution = DigitShapes.NativeNational;
        culture.NumberFormat.NumberNegativePattern = 0;
        return culture;
    }

Originally posted by @OmidAtaei1984 in #1466 (comment)