CODESYS - Runtime polymorphism using inheritance (OOP)

Source code: https://github.com/ATandU?tab=repositories

- Explanation of compile and runtime polymorphism, the object interface and the object property you can fin in the previous video: https://youtu.be/dcSW0X4gM98
- We use a pointer to the base class to point to its child classes. Over the pointer we are invoking the correct method in the child class.
- Inheritance: The capability of a class to derive properties and characteristics from another class is called Inheritance. Inheritance is one of the most important feature of Object Oriented Programming and one of its pillars.
- The class that inherits properties from another class is called Sub class, Child Class or Derived Class.
- The class whose properties are inherited by Sub Class is called Base Class, Parent Class or Super class.
- In the public inheritance we have a special bond between the parent and the child class. The so called „is a” relationship because every thing that applies to the base class objects also applies to the child class objects, because every child class object is a base class object, but not the other way around. Not every base class is a derived class!
- When the implementation of all function cannot be provided in a base class because we don’t know it, we declare such a class as abstract. The class is a pure Interface and can’t be instantiated.
- A abstract method/property in the base class provides only an interface
- A method/property in the base class provides an interface and default implementation
- Access specifier define how the members (attributes and methods) of a class can be accessed.
- Public - members are accessible from outside the class (P_Arg_1 & 2)
- Private - members cannot be accessed (or viewed) from outside the class even in a child class
- Protected - members cannot be accessed from outside the class, however, they can be accessed in inherited classes (P_Res)