Paging - 1   2   3

ADO.NET Interview Questions

1. What is OOPS ?  

The OOPS is refer as Object-Oriented Programming in which programs are considered as a group of objects and each object consider instance of a class.

2. What are basic concepts of OOPS ?  

Following are the concepts of OOPS and are as follows:  

  1. Abstraction
  2. Encapsulation
  3. Inheritance
  4. Polymorphism
3. What is an object ?  

An object is an instance of a class and it has its own state, performance, and identity.

4. What is a class ?

A class is simply a illustration of a type of object and It is the blueprint which defines the details of an object.

5. What is an Abstract Class ?

The Abstract class is a class which cannot be instantiated, it exists widely for inheritance and it necessity be inherited.

Abstract classes cannot be used to instantiate objects; because abstract classes are unfinished, it may hold only explanation of the attributes or functions and resulting classes that inherit this gears it's attributes or functions.

6. What is Encapsulation ?

The Encapsulation is a mechanism to bind the data member and method in the single unite called as Class. In the OOP, Encapsulation can be achived by the class.


A class is a single unite which is collection of data members, methods, propertes and attributes.

7. What is Polymorphism ?

The polymorphism is concept of Object Oriented Programming which is often articulated as single interface with multiple function.


The Polymorphism can perform with both Static and Dynamic. In the static polymorphism, response to the function control at the compile time and In the dynamic polymorphism, the response to the function control at the run-time.

8. What is Inheritance ?

The Inheritance is one of the important concept of Object Oriented Programming. In the process of Inheritance, the user can define the base class with public members and methods/functions which can access in the derived/subclass.


Inheritance increases the reusability of codes which make an impact on the performance of execution of the programme.

9. What are manipulators ?

Manipulators are the methods which can be used in aggregation with the insertion (<<) and extraction (>>) operators on an object.

10. Define a constructor ?

A constructor is a function used to prepare the state of an object, and it grows begged at the time of object construction.

The following are important while working with Constructor:

  • A constructor Name should be same as class name.
  • Do not define a constructor with return type.

Paging - 1   2   3