How to define virtual function? Give example.

How to define virtual function? Give example.
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1 Answer

Answer :

A virtual function is a member function that is declared within a base class and redefined by a derived class.

To define virtual function following syntax is used:

Class baseclass

{

virtual function_name()

{

}

};

Class deriveclass

{

function_name()

{

}

};

Example:

#include<iostream.h>

class Base

{

public:

virtual void show( )

{

cout<<”\n show base”;

}

};

class Derived : public Base{

public:

void show( )

{

cout<<”\nshow derived”;

}

};

void main( )

{

Base B;

Derived D;

Base *bptr;

bptr=&B

bptr→show( );

bptr=&D;

bptr→show( );

}
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