COM+ Unleashed

Inheritance

COM+ enables you to use both interface and implementation inheritance. Using interface inheritance, one interface can inherit methods from another interface. An example of interface inheritance is the IDispatch interface, which inherits the QueryInterface(), AddRef(), and Release() methods from the IUnknown interface.

COM+ also enables you to use implementation inheritances. This type of inheritance enables one COM+ class to inherit an implementation from another COM+ class. Implementation inheritance is not fully implemented in COM+. That is, COM+ classes that inherit an implementation from another COM+ class do not have access to the implementation data of the inherited class. Because of this shortcoming, it is sometimes said that ...