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

Write a c program to input five numbers, Write a C program to input five nu...

Write a C program to input five numbers and print them out on a new line e.g 5, 10, 15, 20, 25 displayed as   5   10   15   20   25 #include stdio.h   void main()   {

#pointers, what is the purpose of pointer ? what is the syntax? how it work...

what is the purpose of pointer ? what is the syntax? how it works?

Car rental project, I need a project on car rental system using c programmi...

I need a project on car rental system using c programming only of college level

Explain the #define directive, The #define Directive The #define direct...

The #define Directive The #define directive explains a macro which is a text string represented by a name. Whenever the pre-processor finds this name in the program, it is repl

How do i allocate multidimensional arrays by new? , Can I free() pointers a...

Can I free() pointers allocated  along with new? Can I delete pointers allocated along with malloc()? A: No. It is completely legal, moral, and wholesome to employ malloc() a

Decode the code, By pressing ‘6’ (i.e. key’6’ one time) on the keypad, the ...

By pressing ‘6’ (i.e. key’6’ one time) on the keypad, the mobile shows ‘m’ on display screen in write text message area .

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