Base class pointer pointing to derived class object
Pointer is a data type that stores the address of other data types.
The pointer of Base Class pointing different object of derived class:
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Approach:
- A derived class is a class which takes some properties from its base class.
- It is true that a pointer of one class can point to other class, but classes must be a base and derived class, then it is possible.
- To access the variable of the base class, base class pointer will be used.
- So, a pointer is type of base class, and it can access all, public function and variables of base class since pointer is of base class, this is known as binding pointer.
- In this pointer base class is owned by base class but points to derived class object.
- Same works with derived class pointer, values is changed.
Below is the C++ program to illustrate the implementation of the base class pointer pointing to the derived class:
C++
// C++ program to illustrate the// implementation of the base class// pointer pointing to derived class#include <iostream>using namespace std;// Base Classclass BaseClass {public: int var_base; // Function to display the base // class members void display() { cout << "Displaying Base class" << " variable var_base: " << var_base << endl; }};// Class derived from the Base Classclass DerivedClass : public BaseClass {public: int var_derived; // Function to display the base // and derived class members void display() { cout << "Displaying Base class" << "variable var_base: " << var_base << endl; cout << "Displaying Derived " << " class variable var_derived: " << var_derived << endl; }};// Driver Codeint main(){ // Pointer to base class BaseClass* base_class_pointer; BaseClass obj_base; DerivedClass obj_derived; // Pointing to derived class base_class_pointer = &obj_derived; base_class_pointer->var_base = 34; // Calling base class member function base_class_pointer->display(); base_class_pointer->var_base = 3400; base_class_pointer->display(); DerivedClass* derived_class_pointer; derived_class_pointer = &obj_derived; derived_class_pointer->var_base = 9448; derived_class_pointer->var_derived = 98; derived_class_pointer->display(); return 0;} |
Output:
Displaying Base class variable var_base: 34 Displaying Base class variable var_base: 3400 Displaying Base classvariable var_base: 9448 Displaying Derived class variable var_derived: 98
Conclusion:
- A pointer to derived class is a pointer of base class pointing to derived class, but it will hold its aspect.
- This pointer of base class will be able to temper functions and variables of its own class and can still point to derived class object.
