One-to-one has-a relationships

In VB, a one-to-one has-a relationship between classes refers to a situation where one class contains an instance of another class as a field or property. This relationship represents an association between the two classes, where the first class directly references an instance of the second class. Here’s an example of a one-to-one has-a relationship in VB:

Public Class Car
    Public Property Engine As Engine
    ' Other car-related properties and methods
End Class
Public Class Engine
    ' Engine-related properties and methods
End Class

In the preceding example, we have two classes: Car and Engine. The Car class has a property called Engine of the Engine type and represents the car’s engine. This relationship indicates that a car has a single engine.

To use this relationship, you would typically create instances of the classes and set the appropriate values:

...