Explain static member functions, C/C++ Programming

Assignment Help:

Static Member Functions

All the objects of the class share static data members of a class. The example above demonstrates how to keep track of all the objects of a class which area in existence. Though, this function uses existing objects to invoke a member function getcount(), which returns the value of the static data member. What if the programme does not require to use objects to invoke this function and still the programme would like to know how many objects have been created? If there is no object how the member function is invoked? Further, as can be seen from the last output, the number of objects (count) remains similar at a given instance no matter which object is used to invoke the member function.  In fact, the use of existing objects, like in the above instance, is not an effective way to access the value of the static data member. A specific object should not be used to refer to this member, as it does not belong to that object; it belongs to the whole class. C++ gives a facility to define static function members, for the similar. That is, to invoke such a function, an object is not needed. It can be invoked with the name of the class. The programme given below illustrates its use.

 

                class counter

                 {

                  public :

                                                counter ();

                                                static int getcount();

 

                  private:

                                static int count;

                };

counter::counter ()

                 {

                                count++;

                 }

 

                int counter::getcount()

                 {

                                 }

 

int counter :: count = 0;        // INITIALIZATION OF  

                                    STATIC MEMBER.

void main()

                 {

                  counter c1,c2;

                                cout << " Count = " << counter :: getcount() << endl;

                                cout << " Count = " << counter :: getcount() << endl;

                  counter c3;

                cout << " Count = " << counter :: getcount() << endl;

 

                  counter c4,c5;

 

                                cout << " Count = " << counter :: getcount() << endl;

                                cout << " Count = " << counter :: getcount() << endl;

                  }

Output:

                Count = 2

                Count = 2

                Count = 3

                Count = 5

                Count = 5

 

 


Related Discussions:- Explain static member functions

Return by reference, Return by reference: The return value of the funct...

Return by reference: The return value of the function must be an address variable.  In following program the function returns the value of x or y and their types are declare

Hep, I need help with a c# program. Do yall help with c sharp

I need help with a c# program. Do yall help with c sharp

Explain input output function, Input Output Most languages have "statem...

Input Output Most languages have "statements" to perform I/O . Though in C and C++ we use "functions" to perform I/O. C++ also has its own I/O mechanism - the cin and cout obje

Program to define an array in c, Program to define an array in c: Writ...

Program to define an array in c: Write a program to define an array and print the value of array. void main() { int a[10]={0,11,21,34,44,75,46,57,88,89},i,j,k; clr

How many non-boundary pits and peaks are on the map, Armed with your functi...

Armed with your function from above, we can do some interesting things. For instance, any pixel where the offsets are both zero is a pit (lower than all surrounding points) .

Expression and their types in cpp, E x p r e s sion and their types: ...

E x p r e s sion and their types: An expression will be in form of mathematical expression with C++ syntax embedded with it. Expressions are of following types which m

Explain the array types, Array types An array is a collection of object...

Array types An array is a collection of objects of a one data type. The individual objects are accessed by their position in the array. This way of accessing is known as indexi

Define generic bitwise operations, Define Generic Bitwise Operations? ...

Define Generic Bitwise Operations? Bitwise operators only work on an incomplete number of types int and char. It turns out there's above one kind of int. In particular there's

When does a name clash occur in c++, A name clash happens when a name is de...

A name clash happens when a name is described in more than one place. For example, two dissimilar class libraries could give two different classes the similar name. If you try to u

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

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

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