Events and user events Windows, user objects, and controls each have a predefined set of events. PFC extends this by defining user events for many PFC objects. Events can accept arguments and may return a value. Unless otherwise qualified, this book uses the word event to refer to all three types. Inheritance Inheritance means that objects can be derived from existing objects, with access to their visual component, data, and code.
Inheritance saves coding time, maximizes code reuse, and enhances consistency.
PFC defines object functions and instance variables as public or protected, depending on the desired degree of outside access. PFC does not use the private access level. In certain cases, PFC defines an instance variable as public, allowing you to access it directly. Polymorphism Polymorphism means that functions with the same name behave differently depending on the referenced object and the number of arguments. How PFC uses object orientation PFC uses all facets of PowerBuilder's object-oriented capabilities.