Page 109 - DCAP404 _Object Oriented Programming
P. 109

Object-oriented Programming




                    Notes          You should see the output as shown below:
                                   Enter the value of x
                                   20
                                   Display the entered number 20

                                   One class can be friendly with another class. Consider two classes, first and second. If the class
                                   first is friendly with the other class second, then the private data members of the class first are
                                   permitted to be accessed by the public members of the class second. But on the other hand, the
                                   public member functions of the class first cannot access the private members of the class second.





                                      Task  The friend declaration can be placed anywhere in the class declaration. Explain.
                                   The following program demonstrates how a class one has granted its friendship to the class two.
                                   The class two is declared friendly in the class one.
                                   #include  <iostream.h>
                                   #include  <conio.h>  .
                                   class  one

                                   {
                                                 friend  class  two;
                                          private:
                                   int  x;
                                          public:
                                   void  getdata();
                                   };

                                   class  two
                                   {
                                          public:
                                   void  disp(one);  .
                                   };
                                          inline  void  one::getdata()
                                   {
                                                 cout  <<“Enter  a  number”  ;
                                                 cin>>x;

                                   }
                                          inline  void  two::disp(one  obj)
                                          {
                                   int  x;







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