Important Short Questions and Answers: C# Basics

1.     Define in brief Object Oriented Principles.

^Ø   OOP is based on three key principles: encapsulation, inheritance, and polymorphism.

^Ø   Encapsulation binds together code and data,

^Ø   Inheritance is the mechanism by which one class can inherit the functionality of another.

^Ø   Polymorphism lets you define one interface that describes a general set of actions.

^Ø   These attributes work together in a powerful way that enables the construction of reliable, reusable, and extensible programs.

2.     What are the applications of C# ?

·        console applications

·        Windows applications

·        Developing windows controls

·        Developing ASP.NET projects

·        Creating Web Controls

·        Providing web services

·        Developing .NET component library

3.     What is c#?

^Ø   C# is Microsoft premium language for .Net development such as Enterprise applications, web applications , windows applications and embedded systems.

^Ø   C# is intended to be a simple, modern, general- purpose , type safe object oriented programming language that enables programmers to quickly and easily build solutions for the Microsoft .Net platform.

^Ø   A programming infrastructure created by Microsoft for building, deploying, and running applications and services that use .NET technologies, such as desktop applications and Web services.

4.     Draw the structure of .Net Framework.

5.  What are boxing and unboxing?

Boxing:

The operation of converting a value type to a reference type is called boxing Example:

int i=123;

object obj=(object)i;

Unboxing: The operation of converting a reference type to a value type is called unboxing.

Example:

Object obj=123; int i=(int)obj;

6.  How C #does differ from Java?

C#

C# allows operator overloading

Methods are non virtual by default

It Support struct type

Support decimal type

Java

Does not include operator overloading

Methods are virtual by default

It does not Support struct type

No unsigned integer types.

7.  Name any four applications that are supported by .Net platform.

^Ø   Console Applications

^Ø Windows Applications ^Ø Creating web controls ^Ø Providing web services

^Ø   Developing .net component library.

8.  Compare value type and reference type.

Value types

Value types hold actual value

Value types are allocated on the stack

Reference Types

Reference types hold references to values stored somewhere in memory

Reference types are allocated on the heap

9.  What are the basic elements of C#?

^Ø   Formatting

^Ø   Designing

^Ø    Naming

^Ø    Packaging

^Ø    Documentation

^Ø    Programming

10.            List out the different types of I/O Commands in c#.

^Ø    Command Line Arguments

^Ø    Readline Method

^Ø    Compilation error

11.            Give the benefits of .NET framework.

^Ø    Simple

^Ø    Consistent

^Ø    Modern

^Ø    Object Oriented

^Ø    Type-safe

12.            Discuss .NET namespaces

The .NET Framework Class Libraries(FCL) are arranged into a logical grouping according to their functionality and usability is called Namespaces.

13. Is it possible to have two main () in a C# code? If so, how it is resolved?

Yes, If the program contains several mains that could be the startup function then you need to specify which to use, either on the command line or in a project properties application startup object.

14.            What are the types of string?

^Ø   Immutable String

^Ø   Mutable String

^Ø   Regular Expression

15.            List out the advantages of using the methods.

^Ø   Reducing duplication of code

^Ø   Decomposing complex problems into simpler pieces.

^Ø   Improving clarity of the code

^Ø   Reuse of code

^Ø   Information hiding

16.            What are the types of branching?

Conditional Branching

Conditional branching is the branching is based on particular condition.

Unconditional Branching

Unconditional branching is the branching without any decision

17. Give the syntax of foreach loop. foreach(type<iteration variable>in list)

{

Statements;

}

18. How is class declared?

Classes are declared by using the keyword class followed by the class name and the set of class members surrounded by curly braces.

Syntax:

[modifiers]class class_name

{

[Class members declaration;]

}

19. How are the class members accessed?

Once the object are created, the dot operator is used to access any class members by using the object name.

Syntax:

To access the variables inside the class

Objectname.variable name;

To call the method inside the class

Objectname.methodname(argument_list)