Monday, May 19, 2008

C++ Abstract Base Class

1 comment

What is Abstract Base Class?

  • Allows the base class to provide only an interface for its derived classes.
  • Prevents anyone from creating an instance of this class.
  • A class is made abstract if atleast one pure virtual function defined.

EXAMPLE: Demonstrate the definition of a abstract base class

#include <iostream>

using namespace std;

class MyInterface {
public:
virtual void Display() = 0;
};

class MyClass1 : public MyInterface {
public:
void Display() {
cout << "MyClass1" << endl;
}
};

class MyClass2 : public MyInterface {
public:
void Display() {
cout << "MyClass2" << endl;
}
};

void main()
{
// MyInterface obj;
// Error E2352 Interface.cpp 26: Cannot create instance of abstract class 'MyInterace' in function main()
// Error E2353 Interface.cpp 26: Class 'MyInterface' is abstract because of 'MyInterface::Display() = 0' in function main()
// *** 2 errors in Compile ***

MyClass1 obj1;
obj1.Display();

MyClass2 obj2;
obj2.Display();
}

OUTPUT:
MyClass1
MyClass2
If You Enjoyed This, Take 5 Seconds To Share It

1 comment:

  1. hello would you please differentiate between abstract class and abstract base class please explain with examples of both.....please....

    ReplyDelete