Page 83 - DCAP404 _Object Oriented Programming
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Object-oriented Programming




                    Notes          They occupy space in memory that keeps its state and is operated on by the defined operations
                                   on the object. Each object contains data and code to manipulate the data. Objects can interact
                                   without having to know details of each other data or code.

                                   4.3.1  Objects as Function Arguments

                                   Like any other data type argument,  objects can  also be passed to  a function.  As you  know
                                   arguments are passed to a function in two ways:
                                   1.  by value

                                   2.  by reference
                                   Objects can also be passed as arguments to the function in these two ways. In the first method, a
                                   copy of the object is passed to the function. Any modification made to the object in the function
                                   does not affect the object used to call the function. The following Program illustrates the calling
                                   of functions by value. The program declares a class integer representing a integer variable x.
                                   Only the values of the objects are passed to the function written to swap them.
                                   #include<iostream.h>

                                   #include<conio.h>
                                   class  integer
                                   {
                                          int  x;
                                   public:
                                          void  getdata()
                                   {
                                                 cout  <<  “Enter  a  value  for  x”;
                                                 cin  >>  x;

                                   }
                                          void  disp()
                                   {
                                                 cout  <<  x;
                                   }
                                          void  swap(integer  a1  ,  integer  a2)
                                   {

                                                 int  temp;
                                                 temp  =  a2.x;
                                                 a2.x  =  al.x;
                                                 a1.x  =  temp;
                                   }
                                   };
                                   main()
                                   {




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