Illustrate the example of constructor, C/C++ Programming

Assignment Help:

A Constructive Example

Consider an example , to model a user-defined data type for  strings. The object simulates a character array ( string ) using a character pointer and an integer variable for its actual size, which can be explained at its run-time. The object doesn't use a character array , as it may impose a limit on the number of characters that can be stored.

e.g.

# include

# include < string.h>

class string

                 {

                  public :

                                string ( char *s);

                                ~string();

                                void putstr();

                  private :

                                char *cptr;

                                int size;

 };

void main(void)

                 {

                  string s1(" Hello student    \n");

                  string s2 = " Welcome to C++   \n";

                  string s3 = string ( " its fun \n");

 

s1.putstr();

                s2.putstr();

                s3.putstr();

 }

 

string::string(char *s)

                 {

                                size = strlen(s);

                                cptr = new char[size + 1];

                                strcpy(cptr,s);

                 }

string::~string()

                 {

                                delete cptr;

                 }

void string::putstr()

                 {

                                cout << cptr;

                 }

The class explained in the above example contains a character pointer, which allocates memory at run-time, after determining the actual size need. This programme demonstrates the use of class along with the constructor and destructor to make a user defined data type String. The constructor function contains a default argument of null character, which will be assigned to the variable cptr in the absence of an actual parameter. The destructor uses the delete operator to release the memory allocated by the constructor .

 


Related Discussions:- Illustrate the example of constructor

Create a program to word count, Create a program WordCount1Main.java doing ...

Create a program WordCount1Main.java doing the following:  For each word in the le word.txt { Create an object of the class Word { Add the object to a set of the type java.uti

Define register variables - low level programming, Define Register Variable...

Define Register Variables - Low Level Programming? The Register variables are a special case of an automatic variable. The Automatic variables are allocated storage in the memo

Array structure, We started off taking about input, output, CPU and memory ...

We started off taking about input, output, CPU and memory devices. Within C we need a method of storing large amounts of data in memory. We have used the idea of variables (pointer

Function declarations and function definitions in cpp, FUNCTIONS It refe...

FUNCTIONS It refers to a subprogram that is meant to do a certain task. It is basically used to execute a set of operations and return information to the main or calling functio

Integral, Write a program to find the area under the curve y = f(x) between...

Write a program to find the area under the curve y = f(x) between x = a and x = b, integrate y = f(x) between the limits of a and b. The area under a curve between two points can b

C programming assignment, good night i have an assignment that i really nee...

good night i have an assignment that i really need help with. i have to create a struct file with tag name book to have members int book_id char isbn[255]

Linked list, program for singly linked list with out header

program for singly linked list with out header

What is the employ of ''using'' declaration?, A: A using declaration makes ...

A: A using declaration makes it possible to employ a name from a namespace without the scope operator.

# Bank Account class, Write a C++ program to test the Bank Account class fo...

Write a C++ program to test the Bank Account class for 10 customers.

Develop online slot video game for facebook, Develop Online Slot Video Game...

Develop Online Slot Video Game for Facebook Prepare an online slot video game for a Facebook promotion in order to draw new visits and Increase the number of "likes" of the Face

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd