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INTRODUCTION
CONTENTS
I.
Why dot Net?
1.
2.
3.
4.
II.
Introduction to Microsoft .Net Framework
Building Blocks in .Net
Drawback of Previous Languages
Understand what is .Net
Introduction to .Net
1.
2.
3.
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Types of Application Architecture
.NET Initiative
.Net Framework
a)
Components of .Net framework
b)
Advantages
c)
Requirements of .NET
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I.
Introduction to .Net Framework & VB.NET
1.
Introduction to Microsoft .Net Framework
(Question: Explain the evolution of .NET = 4 marks)
1. In the year 2000, Microsoft launched its new development environment,
calling it Microsoft Visual Studio .Net. Microsoft .Net, at its core, is very
much similar to J2EE (Java 2 Enterprise Edition),
2. It allows a programmer to run both managed (code managed by the .Net
Runtime) and un-managed code (not managed by the.Net runtime).
3. .Net uses Just – In – Time (JIT) compilers to translate your intermediate
compiled code to native executable code, which significantly improves
performance.
4. .Net also provides 'Platform independence' along with 'Language
Independence'.
5. .Net also provides cross language support, meaning that modules and
components written in different .Net compliant languages can call/use
each other's modules and components.
6. Hence, it is possible to write your class in C#.NET, inherit it in VB.Net and
finally use it in VC++.Net. At the time of this writing, as many as 22
languages are supporting the .Net Platform (including VB.NET, VB, C++,
J#, Cobol, Eiffel, Pascal, FORTRAN, RPG, Smalltalk and others), enjoying
full use of .net runtime and huge Framework class library (FCL).
7. .Net is useful for building variety of Windows applications, web
application, web services, database applications and even embedded
applications (using .Net compact version).
2.
Building blocks of .Net framework
(Question: Explain the building blocks of .Net framework = 4 marks)
1. Before VB .NET, there was VB and before there was VB, there was BASIC.
BASIC stands for Beginner's All-purpose Symbolic Instruction Code.
2. It was developed in 1963 by computer scientists John Kemeny and
Thomas Kurtz in Dartmouth College.
3. It was a general purpose programming language that was intended for
beginners.
4. In 1991, BASIC was infused with its Visual component and became
Visual Basic.
5. The new graphical user interface was pioneered by Alan Cooper.
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6. Visual Basic was not an instant hit at first due to compatibility issues but
it began getting a solid following in the mid to late nineties when
developers started becoming familiar with it. In the new millennium, the
Visual Basic
7. .NET became the successor of the Visual Basic programming languages.
8. Visual Basic .NET is Microsoft's Visual Basic on their .NET framework.
9. Microsoft's .NET framework is composed of preprogrammed code that
users can access anytime.
10. This preprogrammed code is referred to as the class library. The
programs in the class library can be combined or modified in order to
suit the needs of programmers.
11. Programs in .NET run on the CLR or the Common Language Runtime
environment. Regardless of computer, as long as this environment is
present, programs developed in a .NET language will run.
1.
2.
3.
4.
5.
6.
7.
3.
Drawback of Previous Languages
There were days when computer programs were written using
procedural languages like C, COBOL, Pascal, etc.
Code was written around functions, i.e., logic is built to control which
functions to perform.
Then came the Object Oriented Programming (OOP) era where languages
like C++ and Smalltalk became popular.
Their code was written around data, i.e., logic was built by identifying the
data in the system and performing functions around this data. he advent
of the Object Oriented (OO) paradigm made it possible to build, manage,
improve and debug bigger applications using components.
The first commercially successful language to provide such runtime
support was Java by Sun Microsystems (although such runtime support
was present in languages like Smalltalk and even in VB).
Java came with a runtime environment, called the Java Virtual Machine
(JVM), which performs memory management, garbage collection,
checking of runtime data types and memory access.
Java also presented the idea of 'Platform independence' by providing
their JVM implementation for different Operating Systems and H/w so a
compiled java program can run on multiple Operating Systems and h/w.
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4.
Understand What .Net is.
The .Net frame work consists of operating system, common language
runtime, framework class library, ADO.Net and XML Library and .Net
Applications.
(Question: Explain the building of .Net framework = 4 marks)
1. Code execution and deployment is made much simpler for developers.
2. Code execution and deployment is assured to be safe and free from
viruses.
3. Programming models are now similar across different languages.
Choosing a programming language is already up to you.
4. Programming models adhere consistently with object oriented styles
5. The .Net Framework is the combination of layers of CLR, FCL, Data and
XML Classes and our Window, Web applications and Web Services.
6. .NET framework allows programmers and developers to use code on the
.NET framework to aid in the development of their software programs.
Figure 1
II.
Introduction to .Net
1.
Types of Application Architecture
 .NET Framework and Languages
1. .NET Framework page, .NET Framework is designed for cross-language
compatibility.
2. Cross-language compatibility means .NET components can interact with
each other irrespective of the languages they are written in.
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3. An application written in VB .NET can reference a DLL file written in C#
or a C# application can refer to a resource written in VC++, etc.
4. This language interoperability extends to Object-Oriented inheritance.
5. This cross-language compatibility is possible due to common language
runtime.
6. .NET Framework page, when the .NET program is compiled, the output
of the compiler is not an executable file but a file that contains a special
type of code called the Microsoft Intermediate Language (MSIL).
7. This MSIL is a low-level language which is designed to be read and
understood by the common language runtime.
8. Because all .NET executable exist as IL, they can freely operate.
9. The Common Language Specification defines the minimum standards
that .NET language compliers must confirm to.
10. Thus, any code compiled by a .NET complier can interoperate with the
.NET Framework.
11. The Common Type System (CTS) defines the rules concerning data types
and ensures that code is executed in a safe environment.
12. Since all .NET applications are converted to IL before execution all
primitive data types are represented as .NET types.
13. This means that, a VB Integer and a C# int are both represented in IL
code as System.Int32.
14. Because both the languages use a common and inter-convertible type
system, it is possible to transfer data between components and avoid
time-consuming conversions.
 Languages supported by .NET Framework
1. The table below lists all the languages supported by the.NET Framework
and describes those languages.
2. The languages listed below are supported by the .NET Framework up to
the year 2003.
3. In future there may be other languages that the .NET Framework might
support.
Language
Description/Usage
APL
APL is one of the most powerful, consistent and concise
computer programming languages ever devised. It is a
language for describing procedures in the processing of
information. It can be used to describe mathematical
procedures having nothing to do with computers or to
describe the way a computer works.
C++
C++ is a true OOP. It is one of the early Object-Oriented
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programming languages. C++ derives from the C
language.
VC++: Visual C++ is the name of a C++ compiler with an
integrated environment from Microsoft. This includes
special tools that simplify the development of great
applications, as well as specific libraries. Its use is known
as visual programming.
C#
C# called as C Sharp is a full-fledged Object-Oriented
programming language from Microsoft built into the
.NET Framework. First created in the late 1990’s was
part of Microsoft’s whole .NET strategy.
Cobol
COBOL (Common Business Oriented Language) was the
first widely-used high-level programming language for
business applications. It is considered as a programming
language to have more lines of code than any other
language.
Component
Pascal
Component Pascal is a Pascal derived programming
language that is specifically designed for programming
software components.
Curriculum
No information.
Eiffel
Eiffel is an Object-Oriented (OO) programming language
which emphasizes the production of robust software.
Eiffel is strongly statically typed mature Object-Oriented
language with automatic memory management.
Forth
Forth is a programming language and programming
environment. It features both interactive execution of
commands (making it suitable as a shell for systems that
lack a more formal operating system), as well as the
ability to compile sequences of commands into threaded
code for later execution.
Fortran
Acronym for Formula Translator, Fortran is one of the
oldest high-level programming languages that is still
widely used in scientific computing because of its
compact notation for equations, ease in handling large
arrays, and huge selection of library routines for solving
mathematical problems efficiently.
Haskell
Haskell is a computer programming language that is a
polymorphic typed, lazy, purely functional language,
quite different from most other programming languages.
It is a wide-spectrum language, suitable for a variety of
applications. It is particularly suitable for programs
which need to be highly modifiable and maintainable.
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Java Language
The Java language is one of the most powerful
Object-Oriented programming languages developed till
date. It's platform independence (not depending on a
particular OS) feature makes it a very popular
programming language.
Microsoft
JScript
Microsoft JScript is the Microsoft implementation of the
ECMA 262 language specification. JScript is an
interpreted, object-based scripting language. It has fewer
capabilities than full-fledged Object-Oriented languages
like C++ but is more than sufficiently powerful for its
intended purposes.
Mercury
Mercury is a new logic/functional programming
language, which combines the clarity and expressiveness
of declarative programming with advanced static
analysis and error detection features. Its highly
optimized execution algorithm delivers efficiency far in
excess of existing logic programming systems, and close
to conventional programming systems. Mercury
addresses the problems of large-scale program
development, allowing modularity, separate compilation,
and numerous optimization/time trade-offs.
Mondrian
Mondrian is a simple functional scripting language for
Internet applications. It is a functional language
specifically
designed
to
inter-operate with other languages in an OO
environment. Current versions of Mondrian run on .NET.
Mondrian also supports ASP.NET, allowing you to embed
functional language code in web pages along with C#
code.
Oberon
Oberon is a programming language very much like
Modula-2 in syntax but with several interesting features.
It's based on OOP concepts and provides a Windowsbased graphical user interface.
Oz
Oz is a high-level programming language that combines
constraint inference with concurrency. Oz is dynamically
typed and has first-class procedures, classes, objects,
exceptions and sequential threads synchronizing over a
constraint store. It supports finite domain and feature
constraints and has powerful primitives for
programming constraint inference engines at a high
level.
Pascal
Principle objectives for Pascal were for the language to
be efficient to implement and run, allow for the
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development of well-structured and well organized
programs, and to serve as a vehicle for the teaching of
the important concepts of computer programming. The
Prime area of application that Pascal entails is the
learning environment. This language was not really
developed to be used for anything other than teaching
students the basics of programming as it was originally
developed for this purpose.
Perl
Practical Extraction and Report Language, Perl, is a
language optimized for scanning arbitrary text files,
extracting information from those text files, and printing
reports based on that information. It's also a good
language for many system management tasks.
Python
Python is an interpreted, interactive, Object-Oriented
programming language. Python combines remarkable
power with very clear syntax. It has modules, classes,
exceptions, very high level dynamic data types, and
dynamic typing.
RPG
Report Program Generator, RPG, is used for generation
of reports from data files, including matching record and
sub-total reports. RPG is one of the few languages
created for punch card machines that are still in common
use today. RPG or RPG IV is a native programming
language for IBM's iSeries minicomputer system.
Scheme
Scheme is a statically scoped programming language. It
was designed to have an exceptionally clear and simple
semantics and few different ways to form expressions. A
wide variety of programming paradigms, including
imperative, functional, and message passing styles, find
convenient expression in Scheme.
Small Talk
SmallTalk is an expressive language that uses a simple
sub set of human languages, nouns and verbs. Smalltalk
was the first, and remains one of the few, pure object
systems, which simply means that everything in a
Smalltalk program is an object. Smalltalk is generally
recognized as the second Object Programming Language
(OPL).
Standard ML
Standard ML is a safe, modular, strict, functional,
polymorphic programming language with compile-time
type checking and type inference, garbage collection,
exception handling, immutable data types and updatable
references, abstract data types, and parametric modules.
It has efficient implementations and a formal definition
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with a proof of soundness.
Microsoft Visual Visual Basic is a "visual programming" environment for
Basic
developing Windows applications. Visual Basic makes it
possible to develop complicated applications very
quickly. This site is all about Visual Basic.
2.
.NET Initiative
 Importance of .Net Framework
(Question: Give the importance of Using Microsoft .Net = 4 marks)
1. Improved Reliability
2. Increased Performance
3. Developer Productivity
4. Powerful Security
5. Integration with existing Systems
6. Ease of Deployment
7. Mobility Support
8. XML Web service Support
9. Support for over 20 Programming Languages
10. Flexible Data Access
3.
.Net Framework
a) Components of .Net framework
(Question: Explain the Microsoft .Net Frame work and its components =
8 marks)
(Question: Explain the importance of CLR, MSIL, JIT, FCL, CLS, CTS = 8 Marks)
Figure 2
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In the .Net Architecture and the .Net Framework there are different
important terms and concepts which we will discuss one by one:
1.
2.
3.
4.
 Common Language Runtime (CLR)
.Net Common Language Runtime (CLR), also called .Net Runtime in short.
It is a framework layer that resides above the OS and handles the
execution of all the .Net applications.
Our programs don't directly communicate with the OS but go through the
CLR.
Some Intermediate Language code is converted to native code, then the
next time it's needed, the CLR reuses the same (already compiled) copy
without re-compiling.
 MSIL (Microsoft Intermediate Language) Code:
1. .Net Program using any .Net compliant language (like C#, VB.Net,
C++.Net) it does not get converted into the executable binary code but to
an intermediate code, called MSIL or IL, understandable by CLR.
2. MSIL is OS and hardware independent code. When the program needs to
be executed, this MSIL, or intermediate code, is converted to binary
executable code (native code).
3. The presence of Intermediate Language makes possible the Cross
Language Relationship as all the .Net compliant languages produce
similar, standard Intermediate Language code.
 Just In Time Compilers (JITers)
1. Intermediate Language compiled code needs to be executed, CLR
invokes the JIT compilers which compile the Intermediate Language
code to native executable code (.exe or .dll) that is designed for the
specific machine and OS.
2. JITers in many ways are different from traditional compilers as they
compile the Intermediate Language to native code only when desired;
e.g., when a function is called, the Intermediate Language of the
function's body is converted to native code just in time.
3. The part of code that is not used by that particular run is never
converted to native code.
 Framework Class Library (FCL)
1. The .Net Framework provides a huge Framework (or Base) Class
Library (FCL) for common, usual tasks.
2. FCL contains thousands of classes to provide access to Windows API and
common functions like String Manipulation, Common Data Structures,
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IO, Streams, Threads, Security, Network Programming, Windows
Programming, Web Programming, Data Access, etc.
3. It is simply the largest standard library ever shipped with any
development environment or programming language.
1.
2.
3.
4.
5.
1.
2.
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7.
8.
 Common Language Specification (CLS)
.Net Compliant Language' and stated that all the .Net compliant
languages can make use of CLR and FCL. But what makes a language a
'.Net compliant' language?
The answer is the Common Language Specification (CLS). Microsoft has
released a small set of specifications that each language should meet to
qualify as a .Net Compliant Language.
As IL is a very rich language, it is not necessary for a language to
implement all the IL functionality; rather, it merely needs to meet a
small subset of CLS to qualify as a .Net compliant language.
This is the reason why so many languages (procedural and OO) are now
running under the .Net umbrella.
CLS basically addresses language design issues and lays down certain
standards.
 Common Type System (CTS)
.Net also defines a Common Type System (CTS).
Like CLS, CTS is also a set of standards. CTS define the basic data types
that IL understands.
Each .Net compliant language should map its data types to these
standard data types.
This makes it possible for the 2 languages to communicate with each
other by passing/receiving parameters to/from each other.
For example, CTS defines a type, Int32, an integral data type of 32 bits (4
bytes) which is mapped by C# through int and VB.Net through its
Integer data type.
CLR also contains the Garbage Collector (GC), which runs in a lowpriority thread and checks for un-referenced, dynamically allocated
memory space.
If it finds some data that is no longer referenced by any
variable/reference, it re-claims it and returns it to the OS so it can be
used by other programs as needed.
The presence of a standard Garbage Collector frees the programmer
from keeping track of dangling data. Ask any C++ programmer how big a
relief it is!
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 Garbage Collector (GC)
1. CLR also contains the Garbage Collector (GC), which runs in a lowpriority thread and checks for un-referenced, dynamically allocated
memory space.
2. If it finds some data that is no longer referenced by any
variable/reference, it re-claims it and returns it to the OS so it can be
used by other programs as needed.
3. The presence of a standard Garbage Collector frees the programmer
from keeping track of dangling data. Ask any C++ programmer how big a
relief it is!
Figure 3
b) Advantages
 Advantages and Disadvantages of VB.Net
(Question: Give the advantage and disadvantage of VB .Net = 4 marks)
Advantages:
1. You can develop programs faster using the VB .NET programming
language. You have so many resources in the .NET Class Library to take
advantage of. VB .NET has full access to the .NET framework.
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2. It is easier to program using Microsoft development environments like
Visual Studio.
3. It is easier to organize your thoughts in an object-oriented programming
language like VB .NET.
4. There are a lot of books and tutorials to improve your skills in VB .NET.
5. The VB language itself interfaces with Microsoft applications seamlessly
(VBA).
Disadvantages:
1. Debugging is very difficult on the VB .NET programming languages
especially with long codes.
2. You'll spend hundreds of dollars purchasing development tools from
Microsoft (Retail version of Visual Studio costs around $300).
3. VB .NET is most useful for RAD.
4. The VB .NET programming language is most useful for rapid application
development or RAD.
5. If you want to get your programs up and running in a jiffy then you
should use VB .NET.
6. Since VB .NET is more suitable for quick and easy programming, it is not
recommended for the large, enterprise-wide software development
solutions.
7. Debugging and finding your way through long and tangling lines of VB
.NET code will simply give you headaches.
c) Requirements of .NET
 Minimum System Requirements to Install .NET
The minimum requirements are:
RAM: 256 MB (Recommended)
Processor: Pentium II 450 MHz
Operating System: Windows 2000 or Windows XP
Hard Disk Space: 3.5 GB (Includes 500 MB free space on disk)
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