informationmor.blogg.se - C&c alpha group

location pointed to by pointer) and Early binding(Compile time) is done according to the type of pointer, since print() function is declared with virtual keyword so it will be bound at run-time (output is print derived class as pointer is pointing to object of derived class ) and show() is non-virtual so it will be bound during compile time(output is show base class as pointer is of base type ). Late binding(Runtime) is done in accordance with the content of pointer (i.e. In above code, base class pointer ‘bptr’ contains the address of object ‘d’ of derived class. Also, a base class pointer can point to the objects of base class as well as to the objects of derived class.

A class may have virtual destructor but it cannot have a virtual constructor.Ĭompile-time(early binding) VS run-time(late binding) behavior of Virtual FunctionsĬonsider the following simple program showing run-time behavior of virtual functions.Įxplanation: Runtime polymorphism is achieved only through a pointer (or reference) of base class type.

It is not mandatory for the derived class to override (or re-define the virtual function), in that case, the base class version of the function is used.

They are always defined in the base class and overridden in a derived class.

The prototype of virtual functions should be the same in the base as well as derived class.

Virtual functions should be accessed using pointer or reference of base class type to achieve run time polymorphism.

A virtual function can be a friend function of another class.

To complete your preparation from learning a language to DS Algo and many more, please refer Complete Interview Preparation Course. Want to learn from the best curated videos and practice problems, check out the C++ Foundation Coursefor Basic to Advanced C++ and C++ STL Course for foundation plus STL.

ISRO CS Syllabus for Scientist/Engineer Exam.

ISRO CS Original Papers and Official Keys.

GATE CS Original Papers and Official Keys.