Back to Reserved words.
The modifier virtual:
- belongs to object-oriented programming;
- describes a virtual method.
A virtual method must also be implemented (programmed) in the class in which it was declared.
A virtual method can be overwritten in a derived class with the reserved word override.
If a virtual method is to be hidden, the class must be covered with the reserved word Reintroduce.
Type TBody = class private dblHeight : double; public function volume : double; virtual; // This method can be in one of this class // derived class can be hidden or overwritten function surfaceArea double; virtual; // This method must be in one of this class // derived class can be hidden or overwritten end;