using System;

public class Program

{

    public static void Main()

    {

        var date1=new Period("Jan",2014);

        var date2=new Period();

        Console.WriteLine("First Date is {0}",date1);

        Console.WriteLine("Second Date is {0}",date2);

        if(date1==date2)

            Console.WriteLine("First Date is the same as second date value");

        else if(date1<date2)

            Console.WriteLine("First Date is less than the second date value");

        else 

            Console.WriteLine("First Date is greater than the second date value");

    }

}

​

public class Period:IComparable

{

    public Period()

    {

        this.Month="Present";

    }

    public Period(string Month,int Year)

    {

        this.Month=Month;

        this.Year=Year;

    }

    public int CompareTo(object obj)

    {

        if(obj==null)

            return 1;

        Period period = obj as Period;

        if (period != null) 

        {

            if(this.Month=="Present" && period.Month=="Present")

                return 0;

            else if(period.Month=="Present")

                return -1;

            else if(this.Month=="Present")

                return 1;

            else

            {

                DateTime date;

                DateTime periodDate;

                if(!DateTime.TryParse(string.Format("01 {0} {1}",Month,Year),out date))

                    throw new ArgumentException("Instance is not a valid Period!");             

                if(!DateTime.TryParse(string.Format("01 {0} {1}",period.Month,period.Year),out periodDate))

                    throw new ArgumentException("Object is not a valid Period!");

                return date.Date.CompareTo(periodDate.Date);

            }

        }

        else 

           throw new ArgumentException("Object is not a Period");

    }

    public override int GetHashCode()

    {

        if(this==null)

            return 0;

        else

        {

            DateTime date;

            if(!DateTime.TryParse(string.Format("01 {0} {1}",Month,Year),out date))

                throw new ArgumentException("Instance is not a valid Period!");         

            return date.GetHashCode();

        }

    }

    public override bool Equals(object obj)

    {

        return this.CompareTo(obj)==0;

    }

    public static bool operator==(Period left, Period right)

    {

        return left.Equals(right);

    }

    public static bool operator!=(Period left, Period right)

    {

        return !(left==right);

    }

    public static bool operator<(Period left, Period right)

    {

        return left.CompareTo(right)<0;

    }

    public static bool operator>(Period left, Period right)

    {

        return left.CompareTo(right)>0;

    }

    public override string ToString()

    {

        if(string.IsNullOrWhiteSpace(Month))

            return string.Empty;

        else if(Month=="Present")

            return Month;

        else 

            return string.Format("{0} {1}",Month,Year);

    }

    public string Month{get; set;}

    public int Year{get; set;}

}