Dot NET Introduction

                                           What is .NET?

A technology from Microsoft to build any kind of software using choice of language based on software called as .NET Framework.

Types of softwares

1.     Console Applications

2.     Windows Applications

3.     Web Applications

4.     Mobile Applications

5.     Window Services

6.     Web Service

Choice of language

1.     Visual C#

2.     Visual Basic

3.     Visual J#

4.     Visual F#

5.     Ruby.NET

6.     Python.NET

Etc.

Note:

All languages get compiled into a common format called as CIL (Common Intermediate Language)

.cs à CSC.EXE à .exe/.dll (CIL)

.vb à VBC.EXE à .exe/.dll (CIL)

Code written in one language can be reused in another language called interoperability among the languages or cross-language integration.

What is .NET Framework?

A software from Microsoft which provides

1.     Base Class Library (BCL)

a.     A collection of classes for almost any purpose shared by all the languages under .NET

2.     Common Language Runtime (CLR)

a.     A runtime environment to execute the CIL code

3.     Compilers and other tools

It is found under

            C:\Windows\Microsoft.NET\Framework

Versions of .NET Framework

·        1.0

·        1.1

·        2.0

·        3.0

·        3.5

·        4.0

·        4.5

·        4.6

Why dot (.) in .NET?

.NET Framework provides a platform to many languages and technologies and make joined effort better and object oriented model.

1.     VB.NET (language + framework)

2.     Python.NET (language + framework)

3.     ASP.NET (web technology + framework)

4.     ADO.NET (database technology + framework)

Hierarchy under .NET

Assemblies (.DLL/.EXE)

            Namespace

                                    Class/Structure/Enumerator/Interface

                                                Field/Method/Property/Indexer/Delegates

Example

MSCorlib.dll

            System namespace

                        Console class

                                    Write()

                                    WriteLine()

                                    ReadLine()

Example

System.Console.WriteLine("welcome to .NET")

Test Case 1: Language C#

//first.cs

class Test

{

            static void Main()

            {

                        System.Console.WriteLine("Welcome to C#");

            }

}

Compile the code

CSC first.cs à first.exe

Note:

If compiler not found set the PATH

PATH=C:\Windows\Microsoft.NET\Framework\v4.0.30319

Test Case 2: Language VB

'second.vb

class Test

            shared sub Main()

                        System.Console.WriteLine("Welcome to Vb")

            end sub

end class

Compile the code

VBC second.vb à second.exe

Using Integrated Development Environment (IDE)

è Visual Studio 2002

è Visual Studio 2003

è Visual Studio 2005

è Visual Studio 2008

è Visual Studio 2010

è Visual Studio 2012

è Visual Studio 2015

Note:

Use ILDASM.EXE (Intermediate Language De-Assembler) tool to view contents of an assembly