This example is mainly to realize the learning of interfaces. This example introduces: BasePage stores the public information of the page. Default inherits BasePage and uses the IProgramer class library. IProgramer class library: InterfaceTest is the interface used by the page. clsVBProgramer inherits the interface InterfaceTest to implement a The function clsDelphiProgramer inherits the interface InterfaceTest, implements another function clsAbstractClass abstract method, and inherits the implementation of the interface InterfaceTest clsAbstractSubClass abstract method.