Contents
What is virtual function explain in detail?
A virtual function is a member function that you expect to be redefined in derived classes. When you refer to a derived class object using a pointer or a reference to the base class, you can call a virtual function for that object and execute the derived class’s version of the function.
What is the purpose of a virtual function?
A virtual function allows derived classes to replace the implementation provided by the base class. The compiler makes sure the replacement is always called whenever the object in question is actually of the derived class, even if the object is accessed by a base pointer rather than a derived pointer.
What are the virtual functions What are the requirements of virtual function explain with example?
Rules of Virtual Function
- Virtual functions must be members of some class.
- Virtual functions cannot be static members.
- They are accessed through object pointers.
- They can be a friend of another class.
- A virtual function must be defined in the base class, even though it is not used.
What is difference between virtual function and pure virtual function?
A virtual function is a member function of base class which can be redefined by derived class. A pure virtual function is a member function of base class whose only declaration is provided in base class and should be defined in derived class otherwise derived class also becomes abstract.
How to explain the use of virtual functions?
– An ambiguity can arise when several paths exist to a class from the same base class…. Explain the use of Vtable. Explain the use of Vtable – Vtables are used for virtual functions. Its a shortform for Virtual Function Table…. Explain the problem with overriding functions – Overriding of functions occurs in Inheritance.
What happens when a virtual function is inherited?
When a class containing virtual function is inherited, the derived class redefines the virtual function to suit its own needs. Base class pointer can point to derived class object. In this case, using base class pointer if we call some function which is in both classes, then base class function is invoked.
How to create a virtual function in C + +?
To create virtual function, precede the function’s declaration in the base class with the keyword virtual. When a class containing virtual function is inherited, the derived class redefines the virtual function to suit its own needs. Base class pointer can point to derived class object.
How is a virtual function declared in a base class?
A virtual function is a member function that is declared within a base class and redefined by a derived class. To create virtual function, precede the function’s declaration in the base class with the keyword virtual. When a class containing virtual function is inherited, the derived class redefines the virtual function to suit its own needs.