What is copy constructor?
“A copy constructor is used to declare and initialize an object from another object.”
“Constructor which accepts a reference to its own class as a parameter is called copy constructor.“
Look at below code:
item t2(t1);
or
item t2=t1;- The process of initializing through a copy constructor is known as copy initialization.
- Here, t2=t1 will not invoke copy constructor. t1 and t2 are objects, assigns the values of t1 to t2.
- A copy constructor takes a reference to an object of the same class as itself as an argument.
Example:
item(item &t1);The above syntax shows the use of reference to pass object as argument.It is the real concept to show the use of copy constructor.
Example:
#include<iostream.h>
class code
{
int id;
public
code ( ) { } //constructor
code (int a) //constructor
{
id=a;
}
code(code &x)
{
id=x.id;
}
void display( )
{
cout<<id;
}
};
int main( )
{
code A(100);
code B(A);
code C=A;
code D;
D=A;
cout<<” \n id of A :”; A.display( );
cout<<” \nid of B :”; B.display( );
cout<<” \n id of C:”; C.display( );
cout<<” \n id of D:”; D.display( );
}output:
id of A:100
id of B:100
id of C:100
id of D:100
You must log in to post a comment.