Page 129 - DCAP404 _Object Oriented Programming

Object-oriented Programming

Notes 6.3 Dynamic Constructors

Allocation of Memory during the creation of objects can be done by the con structures too.
The memory is saved as it allocates the right amount of memory for each object (Objects are not
of the same size). Allocation of memory to objects at the time of their construction is known as
dynamic construction of objects. New operator is used to allocate memory.
The following program concatenates two strings. The constructor function initializes the strings
using constructor function which allocates memory during its creation.
#include <iostream.h>
#include <string.h>
class string
{
char * name;
intlength;
public:
string 0
{
length = 0;
name = new char [length = 1];
};
string (char*s)
{
length = strlen (s);
name = new char [length + 1];
strcpy(name,s );
};
void display (void)
{
cout<<“\n Name :- “<<name;
};
void join (string & a, string & b)
{
length = a.length + b.length;
delete name;
name = new char [length + 1];
strcpy (name,a.name);
strcat (name,” “);
strcat (name,b.name);
};
};
main()

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