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}

In the above example, the Payroll class has two parameterized constructor functions: one for states that have a state income tax and one for states that do not have a state income tax.

Initialization lists

Initialization lists , or member initialization lists, are another way of assigning initial values to a class’s data members.

An initialization list is placed after a function header’s closing parenthesis, but before the function’s opening curly braces.

Example: Given the simple constructor that assigns parameter values to the Payroll class.

Payroll::Payroll(double dFed, double dState){

dFedTax = dFed;

dStateTax = dState;

};

You can use initialization list to rewrite the above constructor function.

Payroll::Payroll(double dFed, double dState)

:dFedTax(dFed), dStateTax(dState){

};

Parameterized constructors that uses default arguments

To create a parameterized constructor that uses default arguments, we can put the default values at the constructor prototype.

In the following example, the class Employee has a constructor with the prototype:

Employee(const int id = 999, const double hourly = 5.65);

This format provides the constructor function with default values for two arguments. When we create an Employee object, the default values in the constructor function prototype are assigned to the class variables.

Example

#include<iostream.h>

class Employee{

private:

int idNum;

double hourlyRate;

public:

Employee(const int id = 9999, const double hourly = 5.65);

void setValues(const int id, const double hourly);

void displayValues();

};

Employee::Employee(const int id, const double hourly)

{

idNum = id;

hourlyRate = hourly;

}

void Employee::displayValues()

{

cout<<”Employee #<<idNum<<” rate $”<<

hourlyRate<<“ per hour “<<endl;

}

void Employee::setValues(const int id, const double hourly)

{

idNum = id;

hourlyRate = hourly;

}

int main(){

Employee assistant;

cout<<“Before setting values with setValues()”<<endl;

assistant.displayValues();

assistant.setValues(4321, 12.75);

cout<<“After setting values with setValues()”<<endl;

assistant.displayValues();

return 0;

}

The output of the above program:

Before setting values with setValues()

Employee #9999 rate $5.65 per hour

After setting values with setValues()

Employee #4321 rate $12.75 per hour

Destructors

A default destructor cleans up any resources allocated to an object once the object is destroyed. The default constructor is sufficient for most classes, except when you have allocated memory on the heap.

To delete any heap variables declared by your class, you must write your own destructor function.

You create a destructor function using the name of the class, the same as a constructor function, preceded by a tilde ~. Destructor functions cannot be overloaded. A destructor accepts no parameter and returns no value.

A destructor is called in two ways:

- when a stack object loses scope when the function in which it is declared ends.

- when a heap object is destroyed with the delete operator.

The destructor itself does not actually destroy the object – it performs termination house keeping before the system reclaims the object’s memory so that memory may be reused to hold new objects.

Questions & Answers

where we get a research paper on Nano chemistry....?
Maira Reply
nanopartical of organic/inorganic / physical chemistry , pdf / thesis / review
Ali
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
Google
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
hey
Giriraj
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
revolt
da
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
Nasa has use it in the 60's, copper as water purification in the moon travel.
Alexandre
nanocopper obvius
Alexandre
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
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Source:  OpenStax, Programming fundamentals in c++. OpenStax CNX. Jul 29, 2009 Download for free at http://cnx.org/content/col10788/1.1
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