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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

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
ya I also want to know the raman spectra
Bhagvanji
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, Xna game studio. OpenStax CNX. Feb 28, 2014 Download for free at https://legacy.cnx.org/content/col11634/1.6
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