Advanced PowerBuilder

Function Overloading Using Inheritance

If you want to use inheritance to allow function overloading, you must complete two basic tasks:

• Define a base class that contains the basic definition of the function.
• Define another class by inheriting from the base class and alter the function definition in the descendent class to reflect the required overloading.

By performing these steps, you produce two similarly named functions, that share a relationship, and which are organized into a predefined structure, that PowerBuilder understands and can use it when a call to this function name is received. PowerBuilder looks for the appropriate function in the entire object hierarchy, starting from the current level and working towards the top, until it finds the first appropriate version of the function.

Home	Previous Lesson: Function Overloading Next Lesson: Function Overloading Without Using Inheritance