CSI-124 C# Exercise

Create a new Windows Form .NET Framework App

1. In the comments of Form1.CS answer the following questions

• What are the four pillars of object-oriented programming?
• In your own words give a definition for each pillar. It is ok if this is not the most academic explanation, I want to know what these concepts mean to you.
• What is the purpose of encapsulation?
• What is the difference between method hiding and method overriding?
• What is the difference between an abstract class and a concrete class?
• What is an interface?
• Describe a situation where an interface would be useful?
• What is a generic?
• Describe a situation where a generic would be useful?

2. You have been asked to define the OOP class structure for a sales company. The users in their system are one of the following types - Customers, Salesperson, or Admin.

3. They sell products which are one of three categories - Cars, Boats, RVs. Currently all of their products are vehicles, but this may change in the future.

4. They also need an order class which will need customer, salesperson, and a list of products. The order class should be able to call the ProcessPayment() method of the customer, passing the total cost of the List< Product > as a parameter.

5.Add a Class Library .Net Framework to the project with the following classes. Choose the data type you believe is the best fit for the fields.

The User Structure:

• User.cs - Abstract Base Class with the following fields and properties, all other users inherit from this base class
  • _firstName
  • _lastName
  • _password
  • _email
  • _phone
  • Provide properties for get/set access to each of the fields
  • Override the ToString() method to return the properties as a string
• Admin.cs - inherits from user
  • _level : level provides an access code that defines how much access a given admin has to the system
  • provide a Get property for level
  • Override the ToString() method to return the properties as a string
• Customer.cs - inherits from user
  • _cardNumber : payment information
  • bool ProcessPayment(decimal price){} - method that will process a payment for the given price amount. Returns true if payment is successful/false if failed. You can simulate this process no real implementation necessary
  • Override the ToString() method to return the properties as a string
• Salesperson.cs - inherits from user
  • _salesIdNumber : unique ID for each salesperson
  • Override the ToString() method to return the properties as a string

The product structure:

• Product.cs Abstract Base Class with the following fields and properties
  • _productId
  • _price
  • _quantityInStock
  • _make
  • _model
  • Provide properties for get access to make/model and productid.
  • Get and Set Access for price and quantityInStock
  • Override the ToString() method to return the properties as a string
• Vehicle Abstract class for all vehicles - inherits from product
  • _year
  • _mileage
  • Provide properties for get access to year
  • Get and Set Access for mileage
  • Override the ToString() method to return the properties as a string
• Car.cs - inherits from vehicle
  • _type (sports car, van, suv etc)
  • Get Access for Type
  • Override the ToString() method to return the properties as a string
• Boat.cs - inherits from vehicle
• RV.CS - inherits from vehicle

The Order Class :

• _completed - This is a true or false based on whether the order has been completed or not
• Provide Get access to completed
• An order requires a customer, a salesperson, and a List< Product >
  • Extra Credit - Create your order class in such a way that it relies exclusively on interfaces instead of concrete classes.
• Void CompleteOrder() - This method will total up the price of the list< product > and call the ProcessPayment() method of the customer. If the transaction is successful set the _completed field to true.

Generate a class diagram for your object design.

The UI:

• in Form1.cs create at least one Customer and Salesperson and a List< product >
• Provide UI to be able to select a customer, a salesperson, and products
• Provide UI to create a new order and complete the order.
• When the order is completed save the information of the order to a file (you may choose any technique you like).