Visual Basic® 2010 Unleashed

NotInheritable Keyword

There are situations in which you might want to prevent inheritance from your classes. This can be useful if you do not want a client to modify in any way the base object’s behavior and its members. To accomplish this, you simply need to mark a class with the NotInheritable keyword. The following code shows an example of a class that cannot be derived:

As you can see, the BusinessPerson class is marked as NotInheritable and cannot be derived by other classes. It can still inherit from other classes but, obviously, members cannot be marked as Overridable, being not inheritable. Another typical example of not inheritable classes ...