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// Be sure to change the namespace name in both files!

namespace Employees

{

///

/// This class represents an Employee.

///

partial class Employee

{...}

}

Our goal is to create a family of classes that model various types of employees in a company.

Assume that you wish to leverage the functionality of the Employee class to create two new classes

(SalesPerson and Manager). The class hierarchy we will be building initially looks something like

what you see in Figure 6-4.

Figure 6-4.

The initial Employees hierarchy

As illustrated in Figure 6-4, you can see that a SalesPerson “is-a” Employee (as is a Manager).

Remember that under the classical inheritance model, base classes (such as Employee) are used to

define general characteristics that are common to all descendents. Subclasses (such as SalesPerson

and Manager) extend this general functionality while adding more specific behaviors.

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---

For our example, we will assume that the Manager class extends Employee by recording the num-

ber of stock options, while the SalesPerson class maintains the number of sales made. Insert a new

class file (Manager.cs) that defines the Manager type as follows: