What Is .NET

It is a platform neutral framework.

It is a layer between the operating system and the programming language.

.NET is not an operating system and it is not a programming language.

It supports many programming languages including VB.Net,C# etc.

.Net is a new framework for developing web-based and window-based applications within the Microsoft environment.

Microsoft.NET Platform

Microsoft.NET

X

M

L

Internet

Protocols

Built on XML and Internet Protocol

Set of tools and services for developing new generation of software

.NET will run in any browser on any platform

Makes it quick and easy to design, implement, and deploy collaborative web solutions

Microsoft.NET

X

M

L

Internet

Protocols

Separates actual data from presentation

XML was designed to carry data, not to display data

XML tags are not predefined. You must define your own tags

XML stands for EXtensible Markup Language

Microsoft.NET

X

M

L

Internet

Protocols

Microsoft.NET is built existing protocols such as HTTP & SOAP

SOAP is an XML/HTTP-based protocol

SOAP allows access to services, objects,and server in a platform-independent manner

SOAP stands for Simple ObjectAccess Protocol

.NET FRAMEWORK

• The .NET Framework is a software framework forMicrosoft Windows operating systems.

• It includes a large library, and it supportsseveral programming languages which allows languageinteroperability

• It Supports over 40 different programming languages.

• The framework's Base Class Library provides userinterface, data access, database connectivity, webapplication development .

Base Class Library

Common Language Specification

Common Language Runtime

ADO.NET: Data and XML

VB VC++ VC#V

isu

al S

tud

io.N

ET

ASP.NET: Web Forms

JScript …

Windows

Forms

Framework, Languages, And Tools

The .NET framework consists of two parts:-

COMMON LANGUAGE RUNTIME

BASE CLASS LIBRARIES

Common Language Runtime(CLR)

CLR works like a virtual machine in executing all languages.

The purpose of the Common Language Infrastructure, is to

provide a language-neutral platform for application

development and execution,

Provide functionality will not be tied to a single language but

will be available across the many languages supported by the

framework. Microsoft's implementation of the CLI is called

the Common Language Runtime or CLR.

The Common Language Runtime consists of four major components:

Common Type System (CTS)

Defines how types are declared, used and managed in

the runtime.

Common Language Specification (CLS) A set of base rules to which any language should conform

in order to interoperate with other .NET languages

MetadataEmbedded data structures that describes the classes and

class members that are defined in within each assembly

Virtual Execution System

Gives an environment in which code can be executed

handling state, control flow and exception management.

CLR Infrastructure

ASSEMBLIES :- Portable Executable(PE) format

Assembly manifest.

Contains simple text name, Version No , public key token.

Metadata :-– Description of the assembly

– Self describing

– Metadata contains information about the assembly, and is also

used to implement the programming capabilities of .NET

Framework.

– CLR checks the metadata to ensure that the correct method

is called.

Security :- supported by the CLR is called Code Access Security (CAS).

Continue…. It is based on evidence that is associated with a specific

assembly.

– Code Access Security uses evidence to determine the

permissions granted to the code.

– If any assembly is not granted the permission a security

exception is thrown.

Just-In-Time (JIT) Compilation:-– At run time, the CLR uses JIT compilation to compile MSIL to

native machine code for the current platform.

– The CLR manages a pool of memory called the managed heap

– .NET continuously runs a Garbage Collector (GC)

BASE CLASS LIBRARIESNAMESPACE DESCRIPTION

System Provides base data types and almost 100

classes that deal with situations like exception

handling, mathematical functions, and garbage

collection.

System.CodeDom Provides the classes needed to produce source

files in all the .NET languages.

System.Collections Provides access to collection classes such as

lists,Queues, bit arrays, hash tables, and

dictionaries

System.Data Provides classes that allow data access and

manipulation to SQL Server and OLEDB data

sources.

System.Diagnostics Provides classes that allow you to debug

and trace Your application. There are

classes to interact with event logs,

performance counters, & system

processes.

System.Globalization Provides classes that access the global

system

variables, such as calendar display, date

and time settings, and currency display

settings.

System.IO Provides classes that allow access to file

and stream control and manipulation

System.Security Provides classes that allow access to

authentication,authorization, permissions,

and policies.

System.Text Provides classes for working with and

manipulating text strings.

GOALS OF .NET FRAMEWORK

• Based on Web standards and practices

• Extensible

• Easy for developers to use

VERSIONS OF .NET FRAMEWORK

Version Version Number Release Date Visual Studio Default in Windows

1.0 1.0.3705.0 2002-02-13 Visual Studio .NET

1.1 1.1.4322.573 2003-04-24 Visual Studio .NET 2003 Windows Server 2003

2.0 2.0.50727.42 2005-11-07 Visual Studio 2005 Windows Server 2003 R2

3.0 3.0.4506.30 2006-11-06Windows Vista, Windows

Server 2008

3.5 3.5.21022.8 2007-11-19 Visual Studio 2008Windows 7, Windows Server

2008 R2

4.0 4.0.30319.1 2010-04-12 Visual Studio 2010

Languages in the .NET Framework

LANGUAGE DESCRIPTION

Microsoft

Visual Basic .NET

Visual Basic .NET extension of Visual Basic. Visual Basic

.NET supports inheritance, constructors,

polymorphism, overloading, stricter type checking,

Microsoft Visual C#

C# is the first modern component-oriented language in

the C and C++ family. It can be embedded in ASP.NET

pages. Features of this language include classes,

interfaces, operator overloading,

Managed Extensions C++

The Visual C++ upgrade is a managed, minimal

extension to the C++ language. This extension include

garbage collection, single-implementation inheritance,

and multiple-interface inheritance.

Microsoft

Visual J# .NET

J# .NET is a language for Java-language developers who

want to build applications and services for the .NET

Framework. J# .NET is fully integrated with the Visual

Studio.NET IDE

Introduction to C#

WHAT IS C#

• C# (Pronounced as ‘C Sharp’) is a new programming language introduced by Microsoft.

• C# is fully object-oriented language like Java and is the first component-oriented language.

• C# is a simple, modern, object oriented, and type-safe programming language derived from C and C++.

• C# is firmly planted in the C and C++ family tree of languages, and will immediately be familiar to C and C++ programmers.

WHAT IS C#

• C# is Specially designed to work with Microsoft’s .NET Platform.

• C# is designed for building robust , reliable , durable components to handle real- world applications.

• The name “C Sharp” was inspired by musical notation (#)whereas sharp indicates that the written note should be made a half-step higher in pitch.

This is similar to the language name of C++, where “++” indicate that a variable should be incremented by 1

Why C#...

• Not all of the supported languages fit entirely neatly into the .NET Framework, but the one language that is guaranteed to fit in perfectly is C#.

• C# is a successor to C++, has been released in conjunction with the .NET Framework.

• C# design goals:Be Comfortable for C++ Programmer.

Fit cleanly into the .NET Common Language Runtime(CLR)

Simplify the C++ model

Evolution Of C#

C

C++

Java C# VB

Productivity

Characteristics of C#

• Simple

• Consistent

• Modern

• Object-Oriented

• Type – Safe

• Versionable

• Flexible

C# Verses Java

• C# and Java are both languages descended from C and C++.

• Each includes advanced features like garbage collection, which remove some of the low level maintenance task from the programmer.

• Both C# and Java compile initially to an intermediate language:

a) C# to Microsoft Intermediate language(MSIL)

and Java to Java Byte code.

Types of applications developed with c#

• Web Applications

• Window Applications

• Console Applications

First c# program

using System;

class Hello

{

static void Main()

{

Console.WriteLine("Hello, C# world!");

}

}

Elements of c# program

Framework class Library

Namespace

Class

Method

Statement

Data types

C# Data Types

Value Types Reference Types

Predefined

TypesUser-defined

Types

Predefined

Types

User-defined

Types

User-Defined

Types

Predefined

Types

Value Types

Enumerations

Structures

Integer

Real

Boolean

Characters

User-Defined

Types

Predefined

Types

Reference Types

Classes

Arrays

Delegates

Interfaces

Objects

Strings

Boxing & Unboxing

• Boxing

The process of converting from a value type to a reference type is called boxing.

Boxing is an implicit conversion.

Boxing exampleusing System;class Conversion1{

static void Main(){

int num1 = 123;Object obj = num1;Console.WriteLine(num1.ToString());Console.WriteLine(obj.ToString());

}}

• Unboxing

The process of converting from a reference type to a value type is called unboxing.

Unboxing example

using System;

class Conversion1

{

static void Main()

{

Object obj = 123;

int num1 = (int)obj;

Console.WriteLine(num1.ToString());

Console.WriteLine(obj.ToString());

}}

Converting Between Numbers and Strings

• To make a string from a number or a number from a string, you can use the Convert methods.

string s = Convert.ToString (x);float y = Convert.ToSingle (s);

Note that “Single” means a single-precision floating point number.

• Numeric objects also provide various kinds of formatting options to specify the number of decimal places:

float x = 12.341514325f;string s =x.ToString ("###.###"); //gives

12.342

Loops and control structures

• The If Statement

• The Select Case Statement

• The Do While Loop

• The For Loop

The IF Statement

• The if . . .else statement is inherited from C and C++.• The if . . .else statement is also known as a conditional statement

Example:if (res > 25){res = res - 5;Console.WriteLine("Result is more then 25");}else{res = 25;Console.WriteLine("Result is less then 25");}

The Select Case statement

int i = 3;switch(i)

{case1:Console.WriteLine("one");break;case2:Console.WriteLine("two");break;case3:Console.WriteLine("three");break;default:Console.WriteLine("None of the about");break;

} In C# , you can use strings as well

While Loop & Do While Loop

• While Loop:

int i = 0;

while (i<10)

{

Console.WriteLine(i.ToString());

i++;

}

• Do While Loop:

int i = 0;

do

{

Console.WriteLine(i.ToString());

i++;

} while (i<10);

For Loops

for (int i=0; i<10; i++){Console.WriteLine(i.ToString( ) );}

For Each Loop:• The foreach loop enables you to iterate over each

element of an array or each element of a collection.

string[] strArr = {"Mahesh", "Chand", "Test String"};

foreach (string str in strArr)

Console.WriteLine(str);

Classes

In the C#, you define a class by using the class keyword, just as you do in C++. Following the class keyword the class name and curly brackets ({. . .}), as shown here:class Hello{

static void Main(){

Console.WriteLine("Hello, C# World!");}

}

Class Members

Class Members Inheritance

Methods Similar to C++ functions. Methods implement some action that can be performed by an object.

Properties Provide access to a class attribute (a field). Useful forexposing fields in components.

Events Used to provide notification.

Constants Represents a constant value.

Fields Represents a variable of the class

Operators Used to define an expression (+, *,->, ++,[], and so on )

Instance Constructors Methods called during initialization of an object.

Static Constructors Called automatically.

Destructors Called when an object is being destroyed.

Types All local types used in a class.

Class member accessibility types and scopes

ACCESSIBLITY TYPE SCOPE

Public Member is accessible from other programs.

Protected Member is accessible by the containing and its derived classes and types.

Internal Member is accessible only the current program.

Protected internal Member is accessible by the current program and the class derived from the containing class.

Methods

A method can return a value have, a list of parameters, and can be accessed through the class, whereas non - static. Static methods are accessed through the class, whereas non-static methods are accessed through the instance of the class.

Class method example

using System;class myClass{public int Sum(int a, int b){int res = a + b;return res;}}

class TestmyClass{static void Main(){myClass cls = new myClass();int total = cls.Sum(5, 8);Console.WriteLine(total.ToString());}}

Method Overloading

• Methods in C# support function overloading in a similar way as C++.

using System;

class myClass

{

public int Sum(int a, int b)

{

int r = a + b;

return r;

}

public float Sum(float a, float b)

{

float r = a + b;

return r;

}

public long Sum(long a, long b)

{

long r = a + b;

return r;

}

class TestClass

{

static void Main()

{

myClass cls = new myClass();

int t1 = cls.Sum(5,8);

Console.WriteLine("Return integer sum:“ +t1.ToString());

float t2 = cls.Sum(5.1,8.6);

Console.WriteLine("Return float sum:“ +t2.ToString());

}

}