Introduction to .
NET
• Content :
– Introduction to .NET Technology
– Introduction to Web Based Applications
– Introduction to ASP.NET
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Introduction to .NET Technology
What is .NET ?
Microsoft.NET is a Framework
– Microsoft .NET is a Framework which provides a common
platform to Execute or, Run the applications developed in
various programming languages.
– Microsoft announced the .NET initiative in July 2000.
– The main intention was to bridge the gap in
interoperability between services of various
programming languages.
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.NET Framework Objectives
• The .NET Framework is designed to fulfill the following
objectives:
– Provide object-oriented programming environment
– Provide environment for developing various types of
applications, such as Windows-based applications and Web-
based applications
– To ensure that code based on the .NET Framework can
integrate with any other code
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.NET Framework
VB C++ C# JScript …
Common Language Specification
Visual Studio 2008
Windows
ASP.NET ADO.NET
Forms
Base Class Library
(CLR) Common Language Runtime
Operating System
• The .NET Framework consists of:
– The Common Language Specification (CLS)
It contains guidelines, that language should follow so that they
can communicate with other .NET languages. It is also
responsible for Type matching.
– The Framework Base Class Libraries (BCL)
A consistent, object-oriented library of prepackaged
functionality and Applications.
– The Common Language Runtime (CLR)
A language-neutral development & execution environment
that provides common runtime for application execution .
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Common Language Specification
CLS performs the following functions:
• Establishes a framework that helps enable cross-language
integration, type safety, and high performance code
execution
• Provides an object-oriented model that supports the
complete implementation of many programming languages
• Defines rules that languages must follow, which helps
ensure that objects written in different languages can
interact with each other
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.NET Framework Base Class Library
• The Class Library is a comprehensive, object-oriented collection
of reusable types
• These class library can be used to develop applications that
include:
– Traditional command-line applications
– Graphical user interface (GUI) applications
– Applications based on the latest innovations provided by ASP.NET
• Web Forms
• XML Web services
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Common Language Runtime (CLR)
• CLR ensures:
– A common runtime environment for all .NET languages
– Uses Common Type System (strict-type & code-verification)
– Memory allocation and garbage collection
– Intermediate Language (IL) to native code compiler. Which
Compiles MSIL code into native executable code
– Security and interoperability of the code with other
languages
• Over 36 languages supported today
– C#, VB, Jscript, Visual C++ from Microsoft
– Perl, Python, Smalltalk, Cobol, Haskell, Mercury, Eiffel, Oberon, Oz, Pascal, APL,
CAML, Scheme, etc.
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Execution in CLR
Source
code
VB C# C++
Compiler Compiler Compiler
Managed Assembly Assembly Assembly
code IL Code IL Code IL Code
Common Language Runtime
JIT Compiler
Native Code
Operating System Services 10
Visual Studio 2008 IDE
Microsoft has introduced Visual Studio.NET,
which is a tool (also called Integrated Development
Environment) for developing .NET applications by
using programming languages such as VB, C#,
VC++ and VJ#. etc.
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C# (C Sharp)
• Microsoft C# (pronounced C Sharp) developed by Microsoft
Corporation, USA
• New programming language that runs on the .NET Framework
• C# is simple, modern, type safe, and object oriented
• C# code is compiled as managed code
• Combines the best features of Visual Basic, C++ and Java
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C# Features
• Simple
• Modern
• Object-Oriented
• Type-safe
• Versionable
• Compatible
• Secure
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Introduction to Web Based
Applications
Introducing Web Applications
Web Page Static web page
• This type of web page consists of
HTML code typed directly into text
or a web page editor
Static Dynamic • It is saved as an .htm or .html
file
• The content (text, images, hyperlinks, and so on) and
appearance of a static web page is always the same.
• These web pages do not utilize any database or any
other technology that dynamically builds up pages or
content at runtime based on their visitors input.
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How Are Static Web Pages Served ?
WEB SERVER
3. Web Server locates
1. Author
.html file
writes
HTML
4. HTML stream( from the
.html page) returned to
the browser
2. Client requests
the web page
5. Browser processes
HTML and displays
page
CLIENT
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Dynamic web page
• Dynamic Web sites provide its visitors to modify the content of
the web page based on their input.
• They utilize databases and other mechanisms that enable to
– identify their visitors
– present them with customized greeting messages
– restructure the content according to user input etc..
• Examples:
– Online shopping stores,
– search engines
– email
– chat, community portals etc.
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Dynamic web page
• Dynamic Web sites make use of “server-side
technology”.
• Server-side technologies add an extra layer to the
static web page that enables the Web Server to
generate HTML on the fly.
• The web server will first
– interpret the server-side code present in web
pages,
– generate the appropriate HTML and then
– send the response to the web browser.
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How Are Dynamic Web Pages Served?
3. Web Server collects the contents
(code + HTML) of the web page
WEB SERVER and parses the contents to
produce HTML.
2. The Web Server
searches for the
requested page 4. The HTML stream is
sent back to the
requesting browser
1. The Web browser 5. Browser processes
sends a request HTML and displays
page
CLIENT
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Introduction to ASP.NET
Introduction to ASP.NET
ASP.NET is part of the Microsoft .NET framework
ASP.NET is an effective and flexible technology for
creating interactive and dynamic web
pages.
It is a convergence of two major Microsoft technologies:
– Active Server Pages (ASP)
• Active Server Pages is Microsoft’s server side scripting
technology for building dynamic web pages.
– .NET Framework
• The .NET Framework is a suite of technologies designed by
Microsoft where program development takes place.
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Introduction to ASP.NET
It is built on .NET Common Language Runtime
ASP.NET :
Provides better user authentication
Has better language support.
Has a large set of new controls (web controls)
Uses compiled code, which increases the performance of the
applications
It is programmable using any of the .NET languages
(VB.NET, C#, VJ# etc).
The ASP.NET pages are saved with the .aspx
extension. 22
Working of an ASP.NET Application
To execute an ASP.NET file, the
following steps are followed: ASP.NET
1. A web browser sends a Script
request for an ASP.NET file to Engine
the web server by using a
URL.
2. The web server receives the
request and retrieves the WEB
appropriate ASP.NET file from SERVER
the disk or memory.
3. The web server forwards the
file to the ASP.NET script CLIENT
engine for processing.
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Working of an ASP.NET Application
4. The ASP.NET script engine reads
ASP.NET
the file from top to bottom and
executes it.
Script
Engine
5. The processed ASP.NET file is
generated as an HTML
document and the ASP.NET
script engine sends the HTML
WEB
page to the Web server.
SERVER
6. The Web server then sends the
HTML code to the client which
interprets the output and CLIENT
displays it.
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Advantages of ASP.NET
• Easy Programming Model
• Flexible Language Options
• Compiled Execution
• Rich Output Caching
• Web-Farm Session State
• Enhanced Reliability
• Master Pages
• Themes
• Improved Security
• Web Services
• Improved Performance and Scalability
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Visual Studio 2008 IDE
Title Bar
Menu Bar
Tool Box
Document
window
Solution
Explorer
Properties
Window
Status Bar
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Creating a New Web Application
• To start a new Web Application in VS 2008, Click the Create Web Site
button on the Start page or Select File > New > Web Site
• The New Web Site allows
you to choose:
• Templates
• Language for creating an
application
• Location where the application
will be created
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Creating a New Application
(Continued)
▪ After you create a new Web Application, Default.aspx page is added to this
Website. To Rename this page, Select the page from the Website node in the
Solution Explorer > Right Click > Rename.
▪ Files can be added to the Project,
using Solution Explorer:
▪ Right click on the project node, in
the Solution Explorer, and select
the option Add New Item.
▪ The Add New Item window will
popup.
▪ Select the type of file (item) to be
added and click on Add.
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Solution Explorer
▪ Presents a tree view structure of files
present in the project.
– By default a New Website will contain:
• An App_Data folder
• A Default.aspx page (including
Default.aspx.cs)
To view Solution Explorer:
▪ Select View > Solution Explorer
OR
▪ Press buttons Ctrl+W,S
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Solution Explorer (Continued)
▪ The Toolbar at the top of Solution Explorer enables various tasks.
Code
Refresh Copy Website
Properties View
Designer
Nest ASP.NET
Related Configuration
Files
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Toolbox
▪ To add controls in the Design Window use
Toolbox.
▪ There are various tool tabs available in the
Toolbox.
– The controls in the IDE are presented in a
hierarchical manner (e.g., Standard Tab, Data Tab,
Validation, Navigation, WebParts etc.).
– Depending on the type of project (application) the
toolbox tabs will vary.
▪ To view the tool box:
– Select menu View > Toolbox
OR
– Press buttons Ctrl+Alt+X or Ctrl+W, X
▪ You can also view the controls as icons by right-
clicking on the toolbox you want to change and
deselecting the List View.
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Properties Window
▪ To view or change the properties and events of a selected control during
design use the Properties Window
▪ To configure a control:
– Click once to select it
– Press F4 or Select menu View > Properties
window
– Modify the appropriate properties in the window
▪ There are various options provided for viewing
the properties of the selected control, such as:
– Categorized view
– Alphabetical view
– Properties view (default)
– Events View
– Property pages
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Adding an Event
▪ Events can be added to
the code in one of three
ways:
1. Double clicking a control in
design view
2. Typing the code manually
3. Selecting the Events Icon
and double clicking the
required event from the
Properties Window
Event Handler
For Button
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Project Settings
▪ Project Settings can be adjusted using
various options in the Project
Properties menu or by using the
Solution Explorer window.
– These settings change based on the
type of application developed.
▪ Setting Startup Page:
– Right Click on the form you want set as
the startup page in the Solution Explorer.
– Select option Set As Start Page.
▪ Startup Project (In case of multiple
projects):
– Right Click on Project to set as startup
project in the Solution Explorer.
– Select Option Set As StartUp Project.
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Resources
• Visual Studio 2008 Website
http://msdn.microsoft.com/vstudio/
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Questions and Comments
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