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An orderly hierarchy

The C# inheritance mechanism allows you build an orderly hierarchy of classes to supplement the classes that are already in the class library.

When several of your abstract data types have characteristics in common, you can design their commonalities into a single superclass and separate theirunique characteristics into unique subclasses. This is one of the purposes of inheritance.

The airship hierarchy

For example, suppose you are building a program dealing with airships. All airships have altitude and range properties in common. Therefore, you couldbuild a base Airship class containing data and methods having to do with range and altitude.

From this superclass, you could derive a Balloon class and an Airplane class.

The Balloon class

The Balloon class might add properties and methods dealing with passenger capacity and what makes it go up (helium, hydrogen, or hot air) . Objects of the Balloon class would then be able to deal with altitude, range, passenger capacity, and what makes it go up.

The Airplane class

The Airplane class might add properties and methods dealing with engine type (jet or propeller) and cargo capacity. Objects of the Airplane class could then deal with altitude, range, engine type, and cargo capacity.

Three types of objects

Having created this hierarchy of classes, you could instantiate objects of type Airship , Balloon , and Airplane with the objects of each type having properties and methods to deal with those specialcharacteristics of the flying machine indicated by the name of the class.

From the general to the specialized

You may have noticed that in this hierarchical class structure, inheritance causes the structure to grow in a direction from most general to morespecialized. This is typical.

Single and multiple inheritance

C++ and some other object-oriented programming languages allow for multiple inheritance. This means that a new class can extend more than one superclass.This has advantages in some cases, but can lead to difficulties in other cases.

C# does not support multiple inheritance. Instead it supports a different mechanism called an interface that provides most of the benefits ofmultiple inheritance without most of the problems. I will explain the C# interface in a future module.

The ISA relationship

You will sometimes hear people speak of the ISA relationship when discussing OOP (such as in he is a hero) . The source of this terminology is more fundamental than you may at first suspect.

Object-oriented designers often strive to use inheritance to model relationships where a subclass "is a kind of" the superclass. For example, a car "is a kind of" vehicle. A programmer "is a kind of" employee which in turn "is a kind of" person. An airplane "is a kind of" airship and so is a hot-air balloon.

This relationship is called the ISA relationship. It's that simple.

The HASA relationship

If you were to define a class that more fully represents an airplane, you might choose to break certain parts of the airplane out into separate objectsand to incorporate them by reference into your Airplane class.

Questions & Answers

where we get a research paper on Nano chemistry....?
Maira Reply
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
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
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Xna game studio. OpenStax CNX. Feb 28, 2014 Download for free at https://legacy.cnx.org/content/col11634/1.6
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