A pure virtual function (or abstract function) in C++ is a virtual function for which we don't have implementation, we only declare it. A pure virtual function is declared by assigning 0 in declaration..
Keeping this in consideration, what is the difference between virtual and pure virtual function in C++?
The main difference between 'virtual function' and 'pure virtual function' is that 'virtual function' has its definition in the base class and also the inheriting derived classes redefine it. The pure virtual function has no definition in the base class, and all the inheriting derived classes has to redefine it.
One may also ask, can virtual function be inlined C++? Virtual functions can be inlined sometimes. An excerpt from the excellent C++ faq: "The only time an inline virtual call can be inlined is when the compiler knows the "exact class" of the object which is the target of the virtual function call.
Furthermore, can pure virtual function have body C++?
Yes, a pure virtual function can have a body. All pure virtual means is that you can't call the function using an object that has declared or has inherited the pure virtual function. Because of this, you cannot create objects of classes with pure virtual functions.
What is the use of virtual functions?
You use virtual functions when you want to override a certain behavior (read method) for your derived class rather than the one implemented for the base class and you want to do so at run-time through a pointer to the base class.
Related Question Answers
What are pure virtual functions?
A pure virtual function or pure virtual method is a virtual function that is required to be implemented by a derived class if the derived class is not abstract. Classes containing pure virtual methods are termed "abstract" and they cannot be instantiated directly.Why do we need virtual function?
A virtual function is a member function that is declared within a base class and redefined by a derived class. When a class containing virtual function is inherited, the derived class redefines the virtual function to suit its own needs. Virtual Functions are used to support " Run time Polymorphism".When would you use a virtual destructor?
So there will be memory leak for derived object. To be simple, Virtual destructor is to destruct the resources in a proper order, when you delete a base class pointer pointing to derived class object. Virtual base class destructors are "best practice" - you should always use them to avoid (hard to detect) memory leaks.What is a virtual function in C++?
A C++ virtual function is a member function in the base class that you redefine in a derived class. It is declared using the virtual keyword. But, when base class pointer contains the address of the derived class object, always executes the base class function.What is virtual and pure virtual function explain with example?
A pure virtual function or pure virtual method is a virtual function that is required to be implemented by a derived class if the derived class is not abstract. Classes containing pure virtual methods are termed "abstract" and they cannot be instantiated directly.What is pure virtual function in C++?
A pure virtual function is a virtual function in C++ for which we need not to write any function definition and only we have to declare it. It is declared by assigning 0 in the declaration. An abstract class is a class in C++ which have at least one pure virtual function.How do virtual functions work in C++?
Virtual Function in C++ A virtual function is a member function which is declared within a base class and is re-defined(Overriden) by a derived class. Virtual functions ensure that the correct function is called for an object, regardless of the type of reference (or pointer) used for function call.What is virtual function example?
Explain with an example. - 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. - Base class pointer can point to derived class object.Can virtual functions be private in C++?
In C++, virtual functions can be private and can be overridden by the derived class. For example, the following program compiles and runs fine. 1) ptr is a pointer of Base type and points to a Derived class object.What is pure virtual class?
A pure virtual function or pure virtual method is a virtual function that is required to be implemented by a derived class if the derived class is not abstract. Classes containing pure virtual methods are termed "abstract" and they cannot be instantiated directly.What are virtual functions in C++?
C++ virtual function. A C++ virtual function is a member function in the base class that you redefine in a derived class. It is declared using the virtual keyword. It is used to tell the compiler to perform dynamic linkage or late binding on the function.Can abstract class have constructor?
Yes, an abstract class can have a constructor in Java. You can either explicitly provide a constructor to abstract class or if you don't, the compiler will add default constructor of no argument in abstract class. This is true for all classes and it also applies to an abstract class. What is pure virtual method in C++?
C++Server Side ProgrammingProgramming. A pure virtual function is a virtual function in C++ for which we need not to write any function definition and only we have to declare it. It is declared by assigning 0 in the declaration. An abstract class is a class in C++ which have at least one pure virtual function.Can pure virtual function const?
A member function declaration that turns a normal class into an abstract class (i.e., an ABC). You normally only implement it in a derived class. class Shape { public: virtual void draw() const = 0; // = 0 means it is "pure virtual" }; This pure virtual function makes Shape an ABC.What is virtual class in oops?
Virtual class. In object-oriented programming, a virtual class is a nested inner class whose functions and member variables can be overridden and redefined by subclasses of an outer class. Virtual classes are analogous to virtual functions.Can static functions be virtual in C++?
In C++, a static member function of a class cannot be virtual. Also, static member function cannot be const and volatile.Is final a keyword in C++?
Final keyword in C++ when added to a function, prevents it from being overridden by a base class. Also when added to a class prevents inheritance of any type. Consider the following example which shows use of final specifier. This program fails in compilation.What is virtual destructor?
Virtual destructor in base class ensures that the destructor of derived class will be called when using base pointer to the object. Thus derived destructor is not getting called by compiler as it is early/compile time bind. As the type of the object is base, only base destructor is getting called.What is inline function in C++?
Inline function is a function which when invoked requests the compiler to replace the calling statement with its body. A keyword inline is added before the function name to make it inline. It is an optimization technique used by the compilers as it saves time in switching between the functions otherwise. 
