Background
In this blog i have explained OOPS Features of C# in brief to help new comer's to crack an interview,i have explained these feature in brief because of focsing on new comer's to give them a idea how to answer thes questions which are often asked in an interview .
Introduction
The
programming in which data is logically represented in the form of a class and
physically represented in the form an object is called as object oriented
programming (OOP). OOP has the following important features.
In OOP languages it is must
to create a class for representing data. Class contains variables for storing data
and functions to specify various operations that can be performed on data. Class
will not occupy any memory space and hence it is only logical representation of
data.
Within a class variables are
used for storing data and functions to specify various operations
that can be performed on data. This process of wrapping up of data and functions
that operate on data as a single unit is called as data
encapsulation.
Within a class if a member is
declared as
private, then
that member can
not be accessed from out side the class. I.e. that member is
hidden from rest of the program. This process of hiding the details of a class
from rest of the program is called as data abstraction. Advantage of data
abstraction is security.
Class will not occupy any
memory space. Hence to work with the data represented by the
class you must create a variable for the class, which is called as an object.
When an object is created by using the keyword new, then memory
will be allocated for the class in heap memory area, which is called as an
instance and its starting address will be stored in the object in stack memory
area.
When an object is created without
the keyword new, then memory will not be allocated in heap I.e. instance will
not be created and object in the stack contains the value null.
When an object contains null, then it is not possible to access the members of
the class using that object.
Creating a new class from an
existing class is called as inheritance. When a
new class requires same
members as an existing class, then instead of recreating those members the new
class can be created from existing class, which is called as inheritance.
Advantage of inheritance is reusability of the code. During inheritance, the
class that is inherited is called as base class and the class that does the
inheritance is called as derived class.
Polymorphism means having
more than one form. Polymorphism can be
achieved with the help of
overloading and overriding concepts. Polymorphism is classified into compile
time polymorphism and runtime polymorphism.
Summary
I hope this blog is useful for all readers,if you have any suggestion then contact me.