full OOP example program using c# programming : HR information system OOP example

Employee class:

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

namespace Object_Oreineted_Example
{
    internal class Employee
    {
        private int id;
        private string name;
        private int basicSalary;
        private int accomodationAllowance;
        private int foodAllowance;
        private bool gender;
        private int bornyear;
        public Employee() { }   
        public Employee(int id, string name, int basicSalary, int accomodationAllowance, int foodAllowance, string gender, int bornyear)
        {
            this.id = id;
            this.name = name;
            this.basicSalary = basicSalary;
            this.accomodationAllowance = accomodationAllowance;
            this.foodAllowance = foodAllowance;
            setGender(gender);
            this.bornyear = bornyear;
        }
        public void setId(int id)
        {
            this.id = id;
        }
        public void setName(string name)
        {
            this.name = name;
        }
        public void setBasicSalary(int basicSalary)
        {
            this.basicSalary = basicSalary;
        }
        public void setAccomodationAllowance( int accomodationAllowance)
        {
            this.accomodationAllowance=accomodationAllowance;  
        }
        public void setfoodAllowance(int foodAllowance)
        {
            this.foodAllowance=foodAllowance;
        }
        public void setGender(string gender)
        {
            if (gender == "male")
                this.gender = true;
            else if (gender == "female")
                this.gender = false;
            else Console.WriteLine("invalid entry");
        }
        public void setBornyear(int bornyear)
        {
            this.bornyear = bornyear;
        }
        public int getId()
        {
            return id;
        }
        public String getName()
        {
            return name;
        }
        public int getBasicSalary()
        {
            return basicSalary;
        }
        public int getAccomodationAllowance()
        {
            return accomodationAllowance;
        }
        public int getFoodAllowance()
        {
            return this.foodAllowance;
        }
        public string getGender()
        {
            if (this.gender == true)
                return "male";
            else return "female";
        }
        public int getBornyear()
        { 
            return this.bornyear;
        }
        public int getAge()
        {
            return Convert.ToInt32(DateTime.Now.Year.ToString()) - this.bornyear;
        }
        public virtual string toString()
        {
            return "Employee infomation: \n============\nId: "+id+"\nName: "+name+"\nBasic salary: "+basicSalary+"\nGender: "+getGender();
        }
        public virtual double calculateTotalSalary()
        {
            return basicSalary + accomodationAllowance + foodAllowance;
        }
    }
}

HourlyEmployee class:

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

namespace Object_Oreineted_Example
{
    internal class HourlyEmployee: Employee
    {
        private int hourlyRate;
        private int extraWorkedHours;

        public HourlyEmployee() { }
        public HourlyEmployee(int id, string name, int basicSalary, int accomodationAllowance, int foodAllowance, string gender, int bornyear, int hourlyRate, int extraWorkedHours) : base(id, name,basicSalary, accomodationAllowance, foodAllowance, gender, bornyear)
        {
            this.hourlyRate= hourlyRate;
            this.extraWorkedHours= extraWorkedHours;
        }

        public void setHourlyRate(int hourlyRate)
        {
            this.hourlyRate = hourlyRate;
        }
        public int getHourlyRate() { return hourlyRate; }
        public void setExtraWorkedHours(int extraWorkedHours)
        {
            this.extraWorkedHours = extraWorkedHours;
        }
        public int getExtraWorkedHours() { return extraWorkedHours; }

        //overriding the toString() method:
        public override string toString()
        {
            return base.toString() + "\nHourly Rate: " + getHourlyRate()+"\nExtra worked hours: "+getExtraWorkedHours();
        }
        //overriding the calculateTotalSalary() method:
        public override double calculateTotalSalary()
        {
            double totalSalary = base.calculateTotalSalary()+hourlyRate*extraWorkedHours;
            return totalSalary;
        }
    }
}

BonusEmployee Class:

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

namespace Object_Oreineted_Example
{
    internal class BonusEmployee: Employee
    {
        private int employeeClassification;
        public BonusEmployee() { }
        public BonusEmployee(int id, string name, int basicSalary, int accomodationAllowance, int foodAllowance, string gender, int bornyear,int employeeClassification) : base(id, name,basicSalary,accomodationAllowance, foodAllowance, gender,bornyear)
        {
            this.employeeClassification = employeeClassification;
        }
        public String getEmployeeClassification() 
        {
            if (employeeClassification == 1)
                return "manager";
            else if (employeeClassification == 2)
                return "moderate manager";
            else //if (employeeClassification == 3)
                return "operator";

        }
        public void setEmployeeClassification(int employeeClassification) { this.employeeClassification = employeeClassification; }

        //overriding the toString() method:
        public override string toString()
        {
            return base.toString()+"\nClassification: "+getEmployeeClassification();
        }
        //overriding the calculateTotalSalary() method:
        public override double calculateTotalSalary()
        {
            double totalSalary = base.calculateTotalSalary();

            //adding the bonus value:
            if (employeeClassification == 1)//manager
                totalSalary = totalSalary + base.getBasicSalary() * 0.2;
            else if (employeeClassification == 2)//moderate manager
                totalSalary = totalSalary + base.getBasicSalary() * 0.15;
            else if (employeeClassification == 3)//operater
                totalSalary = totalSalary + base.getBasicSalary() * 0.1;
            return totalSalary;

        }
    }
}

Program Class for testing:

using Object_Oreineted_Example;

internal class Program
{
    private static void Main(string[] args)
    {
        Employee []empARR = new Employee[5];
        Console.WriteLine("welcome, now you will start entering data of 5 employees:");
        for (int i = 0; i < empARR.Length; i++)
        {
            Console.WriteLine("what is employee type? press 1 for bonus employee, press 2 for hourly employee:");
            Employee emp=new Employee();
            int choice = Convert.ToInt32(Console.ReadLine());
            if (choice == 1)
            {
                BonusEmployee bemp = new BonusEmployee(); 
                Console.WriteLine("enter employee classification(press 1 for manager, 2 for moderate manager, 3 for operater:");
                bemp.setEmployeeClassification(Convert.ToInt32(Console.ReadLine()));
                emp = bemp;
            }
            else if (choice == 2)
            {
                HourlyEmployee hemp = new HourlyEmployee(); 
                Console.WriteLine("enter employee hourly rate:");
                hemp.setHourlyRate(Convert.ToInt32(Console.ReadLine()));
                Console.WriteLine("enter employee extra worked hours:");
                hemp.setExtraWorkedHours(Convert.ToInt32(Console.ReadLine()));
                emp= hemp;
            }
            else
            {
                Console.WriteLine("invalid entry...you have to retry again...");
                i--;
                continue;
            }
            Console.WriteLine("enter employee id:");
            emp.setId(Convert.ToInt32(Console.ReadLine()));
            Console.WriteLine("enter employee name:");
            emp.setName(Console.ReadLine());
            Console.WriteLine("enter basic salary:");
            emp.setBasicSalary(Convert.ToInt32(Console.ReadLine()));
            Console.WriteLine("enter accomodation allowance:");
            emp.setAccomodationAllowance(Convert.ToInt32(Console.ReadLine()));
            Console.WriteLine("enter food allowance:");
            emp.setfoodAllowance(Convert.ToInt32(Console.ReadLine()));
            Console.WriteLine("enter employee's gender press m for a male or f for a female");
            string gender = Console.ReadLine();
            if (gender == "m")
                emp.setGender("male");
            else if (gender == "f")
                emp.setGender("female");
            else
            {
                Console.WriteLine("invalid entry...you have to retry again...");
                i--;
                continue;
            }
            Console.WriteLine("enter employee's born year: ");
            emp.setBornyear(Convert.ToInt32(Console.ReadLine()));
            empARR[i] = emp;
        }

        //printing the employees info including total salaries
        Console.WriteLine("Now printing employees information:\n======================");
        foreach (Employee emp in empARR)
        {
            Console.WriteLine(emp.toString());
            Console.WriteLine("\ntotal salary is : "+emp.calculateTotalSalary());
            Console.WriteLine("---------------------------");
        }
        Console.ReadKey();
    }
}