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The class being extended or inherited from is often called the base class or the superclass . The new class is often called the derived class or the subclass .

What is inherited?

The subclass inherits the data representation and behavior of the superclass (and all of its superclasses) . However, the subclass can modify the behavior of inherited methods by overriding them, provided that theywere declared virtual by the original author. (That will be one of the topics in a future module on polymorphism.) The subclass can also add new data representation and behavior that is unique to itsown purposes.

The superclass remains viable

A program can instantiate objects of a superclass as well as instantiating objects of its subclasses.From a practical viewpoint, the superclass doesn't even know that it has been extended.

A hierarchy of classes

Inheritance is hierarchical. By that, I mean that a class may be the subclass of one (and only one) other class and may be the superclass of one or more other classes.

The overall inheritance hierarchy has a single root in the System.Object class. In other words, the System.Object class is the common ancestor for every other class.

Members of the System.Object class

The System.object class defines the following eight methods , which are inherited by every other class:

  • Equals - Overloaded. Determines whether two Object instances are equal.
    • Equals(Object) - Determines whether the specified Object is equal to the current Object.
    • Equals(Object,Object) - Determines whether the specified Object instances are considered equal.
  • Finalize - Allows an Object to attempt to free resources and perform other cleanup operations before the Object isreclaimed by garbage collection.
  • GetHashCode - Serves as a hash function for a particular type.
  • GetType - Gets the Type of the current instance.
  • MemberwiseClone - Creates a shallow copy of the current Object.
  • ReferenceEquals - Determines whether the specified Object instances are the same instance.
  • ToString - Returns a String that represents the current Object.

Because these eight methods are inherited by every other class, they are always available for you to use in your code. (Possibly the most frequently usedof these methods is the ToString method.)

The Button class

Moving down a single path in the inheritance hierarchy, we find that the family tree for the Button class in the System.Windows.Forms namespace is as follows:

  • System. Object
  • System.MarshalByRefObject
  • System.ComponentModel.Component
  • System.Windows.Forms.Control
  • System.Windows.Forms.ButtonBase
  • System.Windows.Forms. Button

If you were to examine the documentation for each of the classes in the Button class' family tree, you would probably find that each class is more specialized than its superclass. For example, the Object class is very generic and the Button class is very specialized. Generally speaking, classes become more specialized as you move down thehierarchy beginning with the Object class.

The Object class is the default superclass

When you define a new class, it becomes an immediate subclass of the Object class by default unless you cause your new class to extend some other class.

Questions & Answers

anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
Daniel
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
NANO
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
Tarell
what is the actual application of fullerenes nowadays?
Damian
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
Tarell
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
Virgil
is Bucky paper clear?
CYNTHIA
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
China
Cied
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
many many of nanotubes
Porter
what is the k.e before it land
Yasmin
what is the function of carbon nanotubes?
Cesar
I'm interested in nanotube
Uday
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Mueller 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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