In this C# lab assignment , we modify the payroll application. If the object currently being processed is a BasePlusCommissionEmployee, the application should increase the BasePlusCommissionEmployees base salary by 10%. Complete the following steps to create the new application: a) Modify classes HourlyEmployee and CommissionEmployee to place them in the IPayable hierarchy as derived classes of the version of Employee that implements IPayable. [Hint: Change the name of method Earnings to GetPaymentAmount in each derived class.] b) Modify class BasePlusCommissionEmployee such that it extends the version of class CommissionEmployee created in Part a. c) Modify PayableInterfaceTest to polymorphically process three salariedEmployee, two HourlyEmployee, one CommissionEmployee and two Base- PlusCommissionEmployee. d) Create a menu that allows a user to select one of the following options to display a string representation of each IPayable objects.

1. Sort last name in descending order using IComparable

2. Sort pay amount in ascending order using IComparer

3. Sort by social security number in descending order using a selection sort and delegate

4. Sorting last name in ascending order and pay amount in descending order by using LINQ

Use the following data to test your program:

IPayable[] payableObjects = new IPayable[ 8 ]; payableObjects[ 0 ] = new SalariedEmployee( "John", "Smith", "111-11-1111", 700M ); payableObjects[1] = new SalariedEmployee("Antonio", "Smith", "555-55-5555", 800M); payableObjects[2] = new SalariedEmployee("Victor", "Smith", "444-44-4444", 600M); payableObjects[ 3 ] = new HourlyEmployee( "Karen", "Price", "222-22-2222", 16.75M, 40M ); payableObjects[4] = new HourlyEmployee("Ruben", "Zamora", "666-66-6666", 20.00M, 40M); payableObjects[ 5 ] = new CommissionEmployee( "Sue", "Jones", "333-33-3333", 10000M, .06M ); payableObjects[ 6 ] = new BasePlusCommissionEmployee( "Bob", "Lewis", "777-77-7777", 5000M, .04M, 300M ); payableObjects[7] = new BasePlusCommissionEmployee("Lee","Duarte", "888-88-888", 5000M, .04M, 300M);

HERE IS A ROUGH OUTLINE OF THE CODE GIVEN FOR THIS

public interface IPayable { decimal GetPaymentAmount(); // calculate payment; no implementation } // end interface IPayable _________________________________________ public abstract class Employee { // read-only property that gets employee's first name public string FirstName { get; private set; } // read-only property that gets employee's last name public string LastName { get; private set; } // read-only property that gets employee's social security number public string SocialSecurityNumber { get; private set; } // three-parameter constructor public Employee( string first, string last, string ssn ) { FirstName = first; LastName = last; SocialSecurityNumber = ssn; } // end three-parameter Employee constructor // return string representation of Employee object, using properties public override string ToString() { return string.Format( "{0} {1} social security number: {2}", FirstName, LastName, SocialSecurityNumber ); } // end method ToString } // end abstract class Employee __________________________________________________________ public class HourlyEmployee : Employee { private decimal wage; // wage per hour private decimal hours; // hours worked for the week // five-parameter constructor public HourlyEmployee( string first, string last, string ssn, decimal hourlyWage, decimal hoursWorked ) : base( first, last, ssn ) { Wage = hourlyWage; // validate hourly wage via property Hours = hoursWorked; // validate hours worked via property } // end five-parameter HourlyEmployee constructor // property that gets and sets hourly employee's wage public decimal Wage { get { return wage; } // end get set { if ( value >= 0 ) // validation wage = value; else throw new ArgumentOutOfRangeException( "Wage", value, "Wage must be >= 0" ); } // end set } // end property Wage // property that gets and sets hourly employee's hours public decimal Hours { get { return hours; } // end get set { if ( value >= 0 && value <= 168 ) // validation hours = value; else throw new ArgumentOutOfRangeException( "Hours", value, "Hours must be >= 0 and <= 168" ); } // end set } // end property Hours // calculate earnings; override Employees abstract method Earnings public override decimal Earnings() { if ( Hours <= 40 ) // no overtime return Wage * Hours; else return ( 40 * Wage ) + ( ( Hours - 40 ) * Wage * 1.5M ); } // end method Earnings // return string representation of HourlyEmployee object public override string ToString() { return string.Format( "hourly employee: {0} {1}: {2:C}; {3}: {4:F2}", base.ToString(), "hourly wage", Wage, "hours worked", Hours ); } // end method ToString } // end class HourlyEmployee _____________________________________________ public class CommissionEmployee : Employee { private decimal grossSales; // gross weekly sales private decimal commissionRate; // commission percentage // five-parameter constructor public CommissionEmployee( string first, string last, string ssn, decimal sales, decimal rate ) : base( first, last, ssn ) { GrossSales = sales; // validate gross sales via property CommissionRate = rate; // validate commission rate via property } // end five-parameter CommissionEmployee constructor // property that gets and sets commission employee's gross sales public decimal GrossSales { get { return grossSales; } // end get set { if ( value >= 0 ) grossSales = value; else throw new ArgumentOutOfRangeException( "GrossSales", value, "GrossSales must be >= 0" ); } // end set } // end property GrossSales // property that gets and sets commission employee's commission rate public decimal CommissionRate { get { return commissionRate; } // end get set { if ( value > 0 && value < 1 ) commissionRate = value; else throw new ArgumentOutOfRangeException( "CommissionRate", value, "CommissionRate must be > 0 and < 1" ); } // end set } // end property CommissionRate // calculate earnings; override abstract method Earnings in Employee public override decimal Earnings() { return CommissionRate * GrossSales; } // end method Earnings // return string representation of CommissionEmployee object public override string ToString() { return string.Format( "{0}: {1} {2}: {3:C} {4}: {5:F2}", "commission employee", base.ToString(), "gross sales", GrossSales, "commission rate", CommissionRate ); } // end method ToString ___________________________________ public class BasePlusCommissionEmployee { private decimal baseSalary; // base salary per week // six-parameter constructor public BasePlusCommissionEmployee( string first, string last, string ssn, decimal sales, decimal rate, decimal salary ) { BaseSalary = salary; // validate base salary via property } // end six-parameter BasePlusCommissionEmployee constructor // property that gets and sets // base-salaried commission employee's base salary public decimal BaseSalary { get { return baseSalary; } // end get set { if ( value >= 0 ) baseSalary = value; else throw new ArgumentOutOfRangeException( "BaseSalary", value, "BaseSalary must be >= 0" ); } // end set } // end property BaseSalary // calculate earnings; override method Earnings in CommissionEmployee public override decimal Earnings() { return BaseSalary + base.Earnings(); } // end method Earnings // return string representation of BasePlusCommissionEmployee object public override string ToString() { return string.Format( "base-salaried {0}; base salary: {1:C}", base.ToString(), BaseSalary ); } // end method ToString } // end class BasePlusCommissionEmployee ______________________________________________ public class SalariedEmployee : Employee { private decimal weeklySalary; // four-parameter constructor public SalariedEmployee( string first, string last, string ssn, decimal salary ) : base( first, last, ssn ) { WeeklySalary = salary; // validate salary via property } // end four-parameter SalariedEmployee constructor // property that gets and sets salaried employee's salary public decimal WeeklySalary { get { return weeklySalary; } // end get set { if ( value >= 0 ) // validation weeklySalary = value; else throw new ArgumentOutOfRangeException( "WeeklySalary", value, "WeeklySalary must be >= 0" ); } // end set } // end property WeeklySalary // calculate earnings; override abstract method Earnings in Employee public override decimal Earnings() { return WeeklySalary; } // end method Earnings // return string representation of SalariedEmployee object public override string ToString() { return string.Format( "salaried employee: {0} {1}: {2:C}", base.ToString(), "weekly salary", WeeklySalary ); } // end method ToString } // end class SalariedEmployee ______________________________________________ public class PayrollSystemTest { public static void Main( string[] args ) { // create derived class objects SalariedEmployee salariedEmployee = new SalariedEmployee( "John", "Smith", "111-11-1111", 800.00M ); HourlyEmployee hourlyEmployee = new HourlyEmployee( "Karen", "Price", "222-22-2222", 16.75M, 40.0M ); CommissionEmployee commissionEmployee = new CommissionEmployee( "Sue", "Jones", "333-33-3333", 10000.00M, .06M ); BasePlusCommissionEmployee basePlusCommissionEmployee = new BasePlusCommissionEmployee( "Bob", "Lewis", "444-44-4444", 5000.00M, .04M, 300.00M ); Console.WriteLine( "Employees processed individually: " ); Console.WriteLine( "{0} earned: {1:C} ", salariedEmployee, salariedEmployee.Earnings() ); Console.WriteLine( "{0} earned: {1:C} ", hourlyEmployee, hourlyEmployee.Earnings() ); Console.WriteLine( "{0} earned: {1:C} ", commissionEmployee, commissionEmployee.Earnings() ); Console.WriteLine( "{0} earned: {1:C} ", basePlusCommissionEmployee, basePlusCommissionEmployee.Earnings() ); // create four-element Employee array Employee[] employees = new Employee[ 4 ]; // initialize array with Employees of derived types employees[ 0 ] = salariedEmployee; employees[ 1 ] = hourlyEmployee; employees[ 2 ] = commissionEmployee; employees[ 3 ] = basePlusCommissionEmployee; Console.WriteLine( "Employees processed polymorphically: " ); // generically process each element in array employees foreach ( Employee currentEmployee in employees ) { Console.WriteLine( currentEmployee ); // invokes ToString // determine whether element is a BasePlusCommissionEmployee if ( currentEmployee is BasePlusCommissionEmployee ) { // downcast Employee reference to // BasePlusCommissionEmployee reference BasePlusCommissionEmployee employee = ( BasePlusCommissionEmployee ) currentEmployee; employee.BaseSalary *= 1.10M; Console.WriteLine( "new base salary with 10% increase is: {0:C}", employee.BaseSalary ); } // end if Console.WriteLine( "earned {0:C} ", currentEmployee.Earnings() ); } // end foreach // get type name of each object in employees array for ( int j = 0; j < employees.Length; j++ ) Console.WriteLine( "Employee {0} is a {1}", j, employees[ j ].GetType() ); } // end Main } // end class PayrollSystemTest