Achieving polymorphism: Virtual functions are an important mechanism for achieving polymorphism in object-oriented programming. By defining virtual functions in a base class, derived classes can override these virtual functions, allowing different class objects to exhibit different behaviors when calling the same function.
Implementing dynamic binding means that the calling of virtual functions is determined at runtime, rather than at compile time. This feature of dynamic binding allows the program to call the appropriate function based on the actual type of the object.
Implementing abstract classes: virtual functions can be declared as pure virtual functions in the base class, thereby making the base class an abstract class that cannot be directly instantiated, but can be used as an interface to define other classes.
Implementing interface inheritance: By using virtual functions, an interface class can be defined, and specific classes can inherit from this interface class and implement the virtual functions within the interface, thereby achieving the mechanism of interface inheritance.
