Exceptions

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Exceptions
{
    class Program
    {
        static void Main(string[] args)
        {
            const Int32 MAXEMPLOYEES = 100;
            Employee[] employees = new Employee[MAXEMPLOYEES];
            Int32 employeeCount = 0, sin, age, yearsService;
            char response = 'Y', gender;
            String firstName, lastName;

            do
            {
                Console.WriteLine("Enter employee first name");
                firstName = Console.ReadLine();
                Console.WriteLine("Enter employee last name");
                lastName = Console.ReadLine();
                Console.WriteLine("Enter employee SIN");
                while (Int32.TryParse(Console.ReadLine(), out sin) == false)
                    Console.WriteLine("Input error! Enter employee SIN");
                Console.WriteLine("Enter employee age");
                while (Int32.TryParse(Console.ReadLine(), out age) == false)
                    Console.WriteLine("Input error! Enter employee age");
                Console.WriteLine("Enter employee gender M/F");
                while (Char.TryParse(Console.ReadLine(), out gender) == false)
                    Console.WriteLine("Input error! Enter employee gender M/F");
                gender = Char.ToUpper(gender);
                Console.WriteLine("Enter employee years service");
                while (Int32.TryParse(Console.ReadLine(), out yearsService) == false)
                    Console.WriteLine("Input error! Enter employee years service");
                try
                {
                    employees[employeeCount] = new Employee(firstName, lastName, sin, age, gender, yearsService);
                    employeeCount++;
                    Console.WriteLine("Employee added successfully");
                }
                catch (Exception e)
                {
                    Console.WriteLine(e.Message);
                    Console.WriteLine("Employee not added");
                }
                Console.WriteLine("Enter another employee? Y/N");
                while (Char.TryParse(Console.ReadLine(), out response) == false)
                    Console.WriteLine("Input error! Enter another employee? Y/N");
                response = Char.ToUpper(response);
            }
            while (response == 'Y');
            for (Int32 count = 0; count < employeeCount; count++)
                Console.WriteLine(employees[count].FirstName + " " + employees[count].LastName + " " +
                    employees[count].Sin + " " + employees[count].Age + " " + employees[count].Gender +
                    " " + employees[count].YearsService);
            Console.WriteLine("Goodbye");
            Console.ReadLine();
        }
    }
}


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using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Exceptions
{
    class Employee
    {
        /*
         *  Private encapsulated member data 
         *  _camelCasing
        */
        private String _firstName;
        private String _lastName;
        private Int32 _sin;
        private Int32 _age;
        private Char _gender;
        private Int32 _yearsService;

        /*
         *  Public overloaded constructors 
         *  The first takes 5 arguments
         *  The second takes 6 arguments 
        */
        public Employee(String firstName, String lastName,
            Int32 sin, Int32 age, Char gender)
        {
            FirstName = firstName;
            LastName = lastName;
            Sin = sin;
            Age = age;
            Gender = gender;
            YearsService = 0;
        }

        public Employee(String firstName, String lastName,
           Int32 sin, Int32 age, Char gender, Int32 yearsService)
        {
            FirstName = firstName;
            LastName = lastName;
            Sin = sin;
            Age = age;
            Gender = gender;
            YearsService = yearsService;
        }

        /*
         * Public Accessors - one for each private member variable
         * Each accessor has a set and a get
        */
        public String FirstName
        {
            get
            {
                return _firstName;
            }
            set
            {
                if (value != "")
                    _firstName = value;
                else
                    throw new Exception("First name must not be empty");
            }
        }
        public String LastName
        {
            get
            {
                return _lastName;
            }
            set
            {
                if (value != "")
                    _lastName = value;
                else
                    throw new Exception("Last name must not be empty");
            }
        }
        public Int32 Sin
        {
            get
            {
                return _sin;
            }
            set
            {
                if (IsValidSIN(value) == true)
                    _sin = value;
                else
                    throw new Exception("Invalid SIN");
            }
        }
        private Boolean IsValidSIN(Int32 sin)
        {
            Int32 first, second, third, fourth, fifth, sixth, seventh, eighth, ninth, sum;
            Boolean validSIN = false;
            first = sin / 100000000;
            second = sin % 100000000 / 10000000;
            third = sin % 10000000 / 1000000;
            fourth = sin % 1000000 / 100000;
            fifth = sin % 100000 / 10000;
            sixth = sin % 10000 / 1000;
            seventh = sin % 1000 / 100;
            eighth = sin % 100 / 10;
            ninth = sin % 10;
            sum = first + second * 2 % 10 + second * 2 / 10 + third + fourth * 2 % 10 + fourth * 2 / 10 +
                    fifth + sixth * 2 % 10 + sixth * 2 / 10 + seventh + eighth * 2 % 10 + eighth * 2 / 10;
            if (sum % 10 == 0 && ninth == 0 || 10 - sum % 10 == ninth)
                validSIN = true;
            return validSIN;
        }
        public Int32 Age
        {
            get
            {
                return _age;
            }
            set
            {
                if (value > 0)
                    _age = value;
                else
                    throw new Exception("Age must be greater than zero");
            }
        }
        public Char Gender
        {
            get
            {
                return _gender;
            }
            set
            {
                if (value == 'M' || value == 'F')
                    _gender = value;
                else
                    throw new Exception("Gender must be 'M' or 'F'");
            }
        }
        public Int32 YearsService
        {
            get
            {
                return _yearsService;
            }
            set
            {
                if (value >= 0)
                    _yearsService = value;
                else
                    throw new Exception("Years service must be greater than or equal to zero");
            }
        }
        public Boolean IsEligibleToRetire()
        {
            Boolean EligibleToRetire = false;
            if (Age + YearsService >= 85)
                EligibleToRetire = true;
            return EligibleToRetire;
        }
    }
}