Explain static class members, C/C++ Programming

Assignment Help:

Static Class Members

As we already know all the objects of the class have dissimilar data members but invoke the similar member functions. Though, there is an exception to this rule. If the data member is declared with the keyword static, then only one such data item is formed for the entire class, no matter how many objects it has. Static data members are useful, if all objects of a class must share a common data item. While, the visibility of this data item remains similar, the duration of this variable is for whole lifetime of the program.

For example, such a variable can be particularly useful if an object needs to know how many objects of its kind exist.

class counter

                 {

                  public :

                                                counter ();

                                                int getcount();

  private:

                                static int count;

                };

counter::counter ()

                 {

                count++;

                 }

 

int counter::getcount()

                {

                                return ( count );

                 }

 

     int counter :: count = 0;// INITIALIZATION OF STATIC MEMBER.

 

                void main()

                 {

                  counter c1,c2;

                                cout << " Count = " << c1.getcount() << endl;

                                cout << " Count = " << c2.getcount() << endl;

 

                  counter c3;

                                cout << " Count = " << c3.getcount() << endl;

                  counter c4,c5;

                                cout << " Count = " << c4.getcount() << endl;

                                cout << " Count = " << c5.getcount() << endl;

                  }

 

Output:

 

                Count = 2             // not 1 because 2 objects are already created.

                Count = 2

                Count = 3

                Count = 5

                Count = 5

 

 


Related Discussions:- Explain static class members

What does odbc do in context with php, What does ODBC do in context with PH...

What does ODBC do in context with PHP? PHP supports many databases such as dBase, Microsoft SQL Server, Oracle, etc. however, it also supports databases such as filePro, FrontB

Explain the working of strcmp and strcat function, Explain the working of s...

Explain the working of strcmp and strcat Function? strcmp() : This function is meant to use to compare two strings. The strcmp() function acknowledge two strings as argument

Program to calculate gross pay and tax payable, Study the following table u...

Study the following table used to compute the tax payable by employees in certain organization   Gross Pay                                  Fewer than Three             Three

Write a program that illustrate creation of a data file, Write a Program th...

Write a Program that illustrate creation of a data file? Here is a program to generate a Fibonacci series and write it into a Data file. # include main() { FILE *fpt;

Crossoword puzzle, find wether specific word is inside a pool of word and w...

find wether specific word is inside a pool of word and what is the direction e.g. north

Plugging the memory leak, Problem #1: plugging the memory leak. When you em...

Problem #1: plugging the memory leak. When you employ the "normal" new operator, for example Foo* p = new Foo(), the compiler generates some special code to manage the case while t

How do you know that your class requires virtual destructor, How do you kn...

How do you know that your class requires a virtual destructor? A: If at least your class has one virtual function, you must make a destructor for this class virtual. It will let

C program for reverse the string , C Program for REVERSE THE STRING #i...

C Program for REVERSE THE STRING #include stdio.h> #include conio.h> #include string.h> void main() {           char name[30];           char *s;

C++ programming, I need help programing this... In this exercise, you will ...

I need help programing this... In this exercise, you will create a program for the sales manager at Computer Haven, a small business that offers motivational seminars to local comp

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