What is C# used for? Like other general-purpose programming languages, C# can be used to create a number of different programs and applications: mobile apps, desktop apps, cloud-based services, websites, enterprise software and games. Lots and lots of games. C# (pronounced see sharp)[b] is a general-purpose, high-level multi-paradigm programming language. C# encompasses static typing, strong typing, lexically scoped, imperative, declarative, functional, generic, object-oriented (class-based), and component-oriented programming disciplines.[16] The C# programming language was designed by Anders Hejlsberg from Microsoft in 2000 and was later approved as an international standard by Ecma (ECMA-334) in 2002 and ISO/IEC (ISO/IEC 23270) in 2003. Microsoft introduced C# along with .NET Framework and Visual Studio, both of which were closed-source. At the time, Microsoft had no open-source products. Four years later, in 2004, a free and open-source project called Mono began, providing a cross-platform compiler and runtime environment for the C# programming language. A decade later, Microsoft released Visual Studio Code (code editor), Roslyn (compiler), and the unified .NET platform (software framework), all of which support C# and are free, open-source, and cross-platform. Mono also joined Microsoft but was not merged into .NET.

1. MODULE 1

2. MODULE 1
 Getting started with .NET Framework: Benefits of .NET Framework
Architecture of .NET Framework
 Components of .NET Framework:
CLR, CTS, Metadata and Assemblies,.NET Framework Class Library, Windows
Forms, ASP .NET and ASP .NE T AJAX, ADO .NET,
 Windows workflow Foundation, Windows Presentation Foundation, Windows
Communication Foundation, Widows Card Space and LINQ.

3. Getting started
 .NET is a framework to develop software applications. It was designed and
developed by Microsoft and the first beta version released in 2000.
 It is used to develop applications for web, Windows, phone. Moreover, it
provides a broad range of functionalities
 This framework contains a large number of class libraries known as
Framework Class Library (FCL). The software programs written in .NET are
executed in the execution environment, which is called CLR (Common
Language Runtime). These are the core and essential parts of the .NET
framework.
 This framework provides various services like memory management,
networking, security, memory management, and type-safety.
 The .Net Framework supports more than 60 programming languages such as
C#, VB.NET, J#, JScript.NET, APL, COBOL, Perl, Oberon, ML, Pascal, Eiffel,
Smalltalk, Python, Cobra, ADA, etc.

4.  Common language runtime (CLR) : which is the execution engine that handles
running applications;
 .NET Framework Class Library (FCL): which provides a library of tested,
reusable code that developers can call from their own applications.

5. Benefits
 Memory Management
 Common Type System:
 Extensive Class Library:
 Development Frameworks and Technologies:
 Language Interoperability:
 Version Compatibility:
 Side-by-side execution:
 Multitargeting:

6. There are a number of benefits provided by .Net framework, some of which are mentioned below.
Memory Management:
In many programming languages, programmers are responsible for allocating and releasing memory and for
handling object lifetimes. In .NET Framework applications, the CLR provides these services on behalf of the
application.
Common Type System:
In traditional programming languages, basic types are defined by the compiler, which complicates cross-language
interoperability. In the .NET Framework, basic types are defined by the .NET Framework type system and are
common to all languages that target the .NET Framework.
Extensive Class Library:
Instead of having to write vast amounts of code to handle common low-level programming operations,
programmers can use a readily accessible library of types and their members from the .NET Framework Class
Library.

7. According to estimate, .Net Framework 4.6 consist of 70,000 Classes in Libraries.
Development Frameworks and Technologies:
The .NET Framework includes libraries for specific areas of application
development, such as ASP.NET for web applications, ADO.NET for data access,
and Windows Communication Foundation for service-oriented applications.
Language Interoperability:
Language compilers that target the .NET Framework emit an intermediate code
named Common Intermediate Language (CIL), which, in turn, is compiled at run
time by the common language runtime. With this feature, routines written in one
language are accessible to other languages, and programmers can focus on
creating applications in their preferred language or languages.

8. Version Compatibility:
With rare exceptions, applications that are developed by using a particular version of the .NET
Framework can run without modification on a later version.
Side-by-side execution:
The .NET Framework helps resolve version conflicts by allowing multiple versions of the common
language runtime to exist on the same computer. This means that multiple versions of
applications can also coexist, and that an application can run on the version of the .NET
Framework with which it was built.
Multitargeting:
By targeting the .NET Framework Portable Class Library, developers can create assemblies that
work on multiple .NET Framework platforms, such as Windows 7, Windows 8, Windows 8.1,
Windows 10, Windows Phone, etc

9. Net Framework Architecture
 .Net Framework Architecture is a programming model for the .Net platform
that provides an execution environment and integration with various
programming languages for simple development and deployment of various
Windows and desktop applications.
 It consists of class libraries and reusable components.
 The basic architecture of the .Net framework is as shown below.

11. COMPONENTS
NET Components
 The architecture of .Net framework is based on the following key components;
1. Common Language Runtime
 Common language runtime (CLR) : which is the execution engine that handles
running applications;
The CLR has the following key features:
Exception Handling - Exceptions are errors which occur when the application is
executed.Examples of exceptions are:
 If an application tries to open a file on the local machine, but the file is not present.
 If the application tries to fetch some records from a database, but the connection to the
database is not valid.

12.  Garbage Collection - Garbage collection is the process of removing unwanted
resources when they are no longer required.Examples of garbage collection
are
 A File handle which is no longer required. If the application has finished all
operations on a file, then the file handle may no longer be required.
 The database connection is no longer required. If the application has finished all
operations on a database, then the database connection may no longer be
required.

13. Working with Various programming languages –
 As noted in an earlier section, a developer can develop an application in a
variety of .Net programming languages.
 Language - The first level is the programming language itself, the most
common ones are VB.Net and C#.
 Compiler – There is a compiler which will be separate for each programming
language. So underlying the VB.Net language, there will be a separate VB.Net
compiler. Similarly, for C#, you will have another compiler.
 Common Language Interpreter – This is the final layer in .Net which would be
used to run a .net program developed in any programming language. So the
subsequent compiler will send the program to the CLI layer to run the .Net
application.

14. 2. Class Library
 The .NET Framework includes a set of standard class libraries. A class library
is a collection of methods and functions that can be used for the core
purpose.
 For example, there is a class library with methods to handle all file-level
operations. So there is a method which can be used to read the text from a
file. Similarly, there is a method to write text to a file.
 Most of the methods are split into either the System.* namespaces. (The
asterisk * just means a reference to all of the methods that fall under the
System namespace)
 A namespace is a logical separation of methods

15. 3. Languages
The types of applications that can be built in the .Net framework is classified broadly into the following
categories.
 WinForms – This is used for developing Forms-based applications, which would run on an end user
machine. Notepad is an example of a client-based application.
 ASP
.Net – This is used for developing web-based applications, which are made to run on any browser
such as Internet Explorer, Chrome or Firefox.
 The Web application would be processed on a server, which would have Internet Information Services Installed.
 Internet Information Services or IIS is a Microsoft component which is used to execute an Asp.Net application.
 The result of the execution is then sent to the client machines, and the output is shown in the browser.
 ADO.Net – This technology is used to develop applications to interact with Databases such as Oracle
or Microsoft SQL Server.
Microsoft always ensures that .Net frameworks are in compliance with all the supported Windows
operating systems.

16. NET Common Language Runtime (CLR)
 .NET CLR is a run-time environment that manages and executes the code written in any .NET programming
language.
 It converts code into native code which further can be executed by the CPU.
.NET CLR Functions
Following are the functions of the CLR.
 It converts the program into native code.
 Handles Exceptions
 Provides type-safety
 Memory management
 Provides security
 Improved performance
 Language independent
 Platform independent
 Garbage collection

17. .NET Framework Class Library(FCL)
 .NET Framework Class Library is the collection of classes, namespaces, interfaces
and value types that are used for .NET applications.
It contains thousands of classes that supports the following functions.
 Base and user-defined data types
 Support for exceptions handling
 input/output and stream operations
 Communications with the underlying system
 Access to data
 Ability to create Windows-based GUI applications
 Ability to create web-client and server applications
 Support for creating web services

18. .NET Framework Class Library Namespaces
 Following are the commonly used namespaces that contains useful classes and
interfaces and defined in Framework Class Library.
Namespaces Description
System It includes all common datatypes, string values, arrays
and methods for data conversion.
System.Data, System.Data.Common,
System.Data.OleDb, System.Data.SqlClient,
System.Data.SqlTypes
These are used to access a database, perform
commands on a database and retrieve database.
System.IO, System.DirectoryServices,
System.IO.IsolatedStorage
These are used to access, read and write files.
System.Diagnostics It is used to debug and trace the execution of an
application.
System.Net, System.Net.Sockets These are used to communicate over the Internet when
creating peer-to-peer applications.

19. Metadata and assemlies
 Assemblies form the fundamental units of deployment, version control, reuse,
and security permissions for .NET-based applications.
 An assembly is a collection of types and resources that are built to work
together and form a logical unit of functionality.
 Assemblies take the form of executable (.exe) or dynamic link library (.dll)
files, and are the building blocks of .NET applications.
 . In .NET Framework, assemblies can contain one or more modules. This
allows larger projects to be planned so that several developers can work on
separate source code files or modules, which are combined to create a single
assembly.
 Assemblies are implemented as .exe or .dll files.

20.  Metadata is information about the assemblies, modules, and types that
constitute .NET programs.
 In .NET, metadata is a common mechanism that the .NET runtime, compilers,
and tools all can use.
 Microsoft .NET uses metadata to describe all types that are used and exposed
by the particular .NET assembly.
 In this sense, metadata describes an assembly in detail, including descriptions
of its identity, the types that it references, the type that it exports, and the
security requirements for execution
 Metadata provides enough information for any runtime, tool, or program to
find out literally everything that is needed for component integration.

21. Windows Forms
What Does Windows Forms Mean?
 Windows Forms is a set of managed libraries in .NET Framework designed to
develop rich client applications.
 It is a graphical API to display data and manage user interactions with easier
deployment and better security in client applications.
Windows Forms offers an extensive client library providing interface to access
native Windows graphical interface elements. It is built with event-driven
architecture similar to Windows clients and hence, its applications wait for
user input for its execution.

22. ASP .NET and Ajax
What is AJAX?
 AJAX = Asynchronous JavaScript and XML.
 AJAX is a technique for creating fast and dynamic web pages.
 AJAX allows web pages to be updated asynchronously by exchanging small
amounts of data with the server behind the scenes. This means that it is
possible to update parts of a web page, without reloading the whole page.
 Classic web pages, (which do not use AJAX) must reload the entire page if the
content should change.
 Examples of applications using AJAX: Google Maps, Gmail, Youtube, and
Facebook tabs.

23. ASP.NET is the web development model and AJAX is an extension of ASP.NET for
developing and implementing AJAX functionality. ASP.NET AJAX contains the
components that allow the developer to update data on a website without a
complete reload of the page.

24.  ADO.NET
ADO.NET is a module of .Net Framework, which is used to establish a connection
between application and data sources. Data sources can be such as SQL Server
and XML. ADO .NET consists of classes that can be used to connect, retrieve,
insert, and delete data.

25.  It is a module of .Net Framework which is used to establish connection
between application and data sources. Data sources can be such as SQL Server
and XML. ADO.NET consists of classes that can be used to connect, retrieve,
insert and delete data.
 All the ADO.NET classes are located into System.Data.dll and integrated with
XML classes located into System.Xml.dll.
 ADO.NET has two main components that are used for accessing and
manipulating data are the .NET Framework data provider and the DataSet.

26. Windows Communication Foundation
 WCF stands for Windows Communication Foundation. The elementary feature
of WCF is interoperability. It is one of the latest technologies of Microsoft that
is used to build service-oriented applications.
 Windows Communication Foundation (WCF) is a framework for building
service-oriented applications. Using WCF, you can send data as asynchronous
messages from one service endpoint to another. A service endpoint can be
part of a continuously available service hosted by IIS, or it can be a service
hosted in an application. An endpoint can be a client of a service that
requests data from a service endpoint
 WCF was released for the first time in 2006 as a part of the .NET framework
with Windows Vista, and then got updated several times. WCF 4.5 is the most
recent version that is now widely used.

27. A WCF application consists of three components −
 WCF service,
 WCF service host, and
 WCF service client.
WCF platform is also known as the Service Model.

28. Advantages of WCF
 It is interoperable with respect to other services.
 WCF services offer enhanced reliability as well as security
 Implementing the security model do not require a major change in coding.
Just a few configuration changes is required to meet the constraints.
 WCF has built-in logging mechanism whereas in other technologies, it is
essential to do the requisite coding.
 WCF has integrated AJAX and support for JSON (JavaScript object notation).
 It offers scalability and support for up-coming web service standards.
 It has a default security mechanism which is extremely robust.

29. Windows Presentation Foundation
WPF stands for Windows Presentation Foundation. It is a powerful framework for
building Windows applications.
WPF was first introduces in .NET framework 3.0 version, and then so many other
features were added in the subsequent .NET framework versions.
WPF – Features
 WPF is a powerful framework to create Windows application. It supports many
great features, some of which have been listed below −

30. Feature Description
Control inside a Control Allows to define a control inside another control as a content.
Media services Provides an integrated system for building user interfaces with common media
elements like images, audio, and video.
Templates In WPF you can define the look of an element directly with a Template
Animations Building interactivity and movement on user Interface
Alternative input Supports multi-touch input on Windows 7 and above.
Direct3D Allows to display more complex graphics and custom themes

31. Windows Workflow Foundation (WF)
Windows Workflow Foundation (WF)
Windows Workflow Foundation (WF) is a Microsoft technology that provides an API,
an in-process workflow engine, and a rehostable designer to implement long-
running processes as workflows within .NET applications.

32.  A workflow is a streamlined flow of multiple processes which when
completed leads to the finished state of a project.
 A workflow engine is a software application designed to help users enforce a
series of recurring tasks that make up a 'business process' or a 'workflow'.

33. LINQ (Language Integrated Query)
It is a query language, introduced in .NET 3.5 framework.
It is used to make the query for data sources with C# or Visual Basics
programming languages.

34. Windows card space
 Windows CardSpace, previously known by its code name, InfoCard, is
the identity management component in .NET 3.0.
 With CardSpace, end users create a digital file on their own computer that
includes user-specific information, like a work phone number, e-mail address
 Users are able to save several different profiles and use whichever profile is
appropriate for a certain situation.

35.  Windows CardSpace was developed by Microsoft as a software program for
the Identity Metasystem.
 CardSpace was used to create digital identities for users, storing some
personal information about them that could be requested and accessed by
websites or other software applications. Users also had the ability to create
personal cards as well, utilizing up to 14 fields to store information.
 When users' information, or identity, was requested, the CardSpace UI would
appear, looking somewhat like a business card with information about the
user. The user can select what card to make available to a website or
application, which results in the website or application requesting a digitally
signed XML token. This token would then contain the information being
requested about the user.