14-1 Use inheritance with the Inventory Maintenance application
In this exercise, you'll add two classes to the Inventory Maintenance application that
inherit the Invltem class. Then, you'll add code to the forms to provide for these new
classes.
1. Open the InventoryMaintenance project in the Extra Exercises\Chapter
14\InventoryMaintenance directory. review the code for the New Item
form to see that the items in the combo box and the label for the combo box
depend on which radio button is selected.
2. Display the Invltem Class and modify the GetDisplayText method so it's
overridable
3. Add a class named Plant that inherits the Invltem class. This new class should
add a string property named Size. It should also provide a default constructor and
a constructor that accepts four parameters (item number, description, price, and
size) to initialize the class properties. This constructor should call the base class
constructor to initialize the properties defined by that class. Finally, this class
should override the GetDisplayText method to add the size in front of the
description, as in this example:
3245649 1 gallon Agapanthus ($7.95)
4. Add another class named Supply that inherits the Invltem class and adds a string
property named Manufacturer _ Like the Plant class, the Supply class should
provide a default constructor and a constructor that accepts four parameters, and
it should override the GetDisplayText method so the manufacturer is added in
front of the description like this:
9210584 Ortho snailpellets ($12_95)
Modify the event handler for the Click event of the Save button on New Item
form so it creates a new item of the appropriate type using the data entered by the
user. Test the application by adding at least one of each type of inventory item
