Is it possible to make a date datatype accept 13 as a month and 30 for all months?

[ashukite]

I am in ethiopia and we have 13 monthes. 12 of them with 30 days each and 13th month with 5 or 6 days. I want to sort my data by date using the bindingsource sort method. But to do that I need to set my date field a date data type. When i set the datatype to date, i can't enter some values like 13 for the month value and 30 for day value of 2nd month.

What I want is just to make my application accept 13 as a month and 30 as a day for all monthes, so that i can sort my data by date. Is it possible to do so by setting culture for my application or by some other means? please help?

[apegram]

System.Globalization has support for many calendars of the world, but I don't know if an Ethiopian calendar is among them. You may need to define your own struct to represent a date. The following code sample is in C#, and I apologize but I do not have a moment to create a VB alternate. But perhaps you or someone else can.

static void Main(string[] args)
        {
            List<EthiopianDate> dates = new List<EthiopianDate>();
            dates.Add(new EthiopianDate(2009, 13, 4));
            dates.Add(new EthiopianDate(2005, 1, 25));
            dates.Sort();

            foreach (EthiopianDate date in dates)
                Console.WriteLine(date.ToString());

            Console.Read();
        }

        struct EthiopianDate : IComparable<EthiopianDate>
        {
            public EthiopianDate(int year, int month, int day)
            {
                this.year = year;
                this.month = month;
                this.day = day;
            }

            private readonly int year;
            private readonly int month;
            private readonly int day;

            public int Year { get { return year; } }
            public int Month { get { return month; } }
            public int Day { get { return day; } }

            public override string ToString()
            {
                string temp = this.Year.ToString()
                    + "-" + this.Month.ToString("00")
                    + "-" + this.Day.ToString("00");
                return temp;
            }

            public int CompareTo(EthiopianDate otherDate)
            {
                if (this.Year > otherDate.Year)
                    return 1;
                else if (this.Year == otherDate.Year && this.Month > otherDate.Month)
                    return 1;
                else if (this.Year == otherDate.Year && this.Month == otherDate.Month && this.Day > otherDate.Day)
                    return 1;
                else if (this.Year == otherDate.Year && this.Month == otherDate.Month && this.Day == otherDate.Day)
                    return 0;
                else
                    return -1;
            }
        }