Session 01
Module 1: Introduction to C#
Module 2: Variables and Data Types
1
Module1 - Objectives
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Describe the .NET Framework
List the other components of .NET Framework
Explain CLR and MSIL
Define Memory Management and Garbage
Collection
Describe the Microsoft Visual Studio 2005
product
Learn the key elements of Visual Studio 2005
IDE
List the basic features of C#
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Architecture of .Net Framework(1)
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The .Net Framework is a multi-lingual
environment to build, deploy and run
applications
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It enables programmers to develop
applications for various platform such as
mobile
devices,
desktop
computer,
smartphones and so on.
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Architecture of .Net Framework(2)
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The .Net Framework architecture
comprises of following:
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Languages included in the .Net Framework
.Net Framework class library (FCL)
The Common Language Runtime(CLR)
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Architecture of .Net Framework(3)
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Other importance components in .Net Framework
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Web Forms
Web services
Windows Forms
ASP.NET
ADO.NET
XML Classes
Base Framework Classes
Common Language Specification
Common Type System
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Microsoft Intermediate Language(MSIL)

When code written in .Net Framework
language such as C#,VB…is complied,
output code is in the form of Microsoft
Intermediate Language(MSIL)
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Common Language Runtime(CLR)
When a code is executed for first time, the
MSIL code is converted to a code native to
operating system.
 This is done ar runtime by the Just-inTime(JIT) compiler present in CLR.
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Basic Features of C#
Object-oriented programming language
 Type safety checking
 Garbage collection
 Standarbisation by ECMA(European
Computer Manufacturers Association)
 Generic Types and Methods
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Visual Studio 2005(1)
Visual studio 2005 is complete set of
development tools to build desktop
applications, web application, XML web
service and mobile applications.
 Primary advantages are:
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Development of applications for .Net Framework
2.0
Development of applications for handheld devices
using .Net Compact Framework 2.0
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Visual Studio 2005(2)
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Key elements of VS 2005
Solution Explorer
 Code Editor
 Properties Window
 Dynamic help
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Write and run first console application
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Step 1: Create new project
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Write and run first console application
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Step 2:Compile program
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You can compile console application from
command line or use IDE
If compile program from command line:
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Edit PATH variable, add following line in PATH
C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727;
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in command line window, change to directory of
program and type: csc <fileName.cs>
If use IDE, press F6 to compile program
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Write and run first console application
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Step 3: Run program
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If use command line window, type .exe file name
If use IDE, press Ctrl + F5
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Module 1 – Summary (1)
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.Net Framework is multi-language platform to build,
deploy and run various types of applications
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Two major components of .Net Framework is CLR
and FCL
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When code is written in .Net language such as
C#,VB…compiled, output code is converted to code
native to operating system by Just-In-Time language
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Module 1 – Summary (2)
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C# is an object-oriented programming language
derived from c and C++.
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C# support features like type-safety checking,
garbage collection, ECMA standardization, generics
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Visual studio 2005 is complete set of tool to build
high performance applications
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Module 2 - Objectives
Identify basic data types in C#
 Explain XML source code documentation
 List the keywords in C#
 Describe reference data types
 Constants and Literals
 Describe console output methods in C#
 Explain number and datetime format
specifiers
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Variables
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A variable is an entity whose value can keep
changing
Declaration syntax:
<datatype> <variableName>
[,variableName=<value>];
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Assignment syntax:
<variable> = <value>;
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Data Types (1)
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In C#, data types are also divided into two
categories:
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Value types:
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Can be either the built-in data type or a user-defined
data type.
Stack storage results in faster memory allocation to
variables of value types
Reference types:
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Variables of reference type store the memory address
of other variables in a heap.
Most of user-defined data types such as class are
reference types.
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Data Types (2)
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Predefined Data Types (1)
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The predefined data types are referred to as
basic data types in C#.
These data types have a predefined range
and size.
The size of the data type helps the compiler
to allocate memory space and ensure the
value assigned is within the range of the data
type.
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Predefined Data Types (2)
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Reference Data Type Classification
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Reference types can be classified as
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Some Reference Data Types
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Variable Naming Rules
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Comments
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Comments are given by programmer to provide
information about a piece of code.
Comments make the program more readable.
Comments help the programmer to explain the purpose
of using a particular variable, method, class, or code
snippet.
Comments are ignored by the compiler during the
execution of the program.
C# supports three types of comments:
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Single-line comments
Multiple-line comments
XML comments
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XML Documentation
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In C#, we can create an XML document that will contain all the XML
comments.
This document is useful when multiple programmers want to view
information of the program.
To create an XML document, we must use the VS 2005 command
prompt window.
csc /doc:<XMLfilename.xml> <CSharpfilename.cs>
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Predefined XML Tags
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XML comments are inserted in XML tags. These tags
can either be predefined or user-defined.
XML comments begin with three forward slashes (///)
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Constants
Constants are fixed values assigned to
identifiers that are not modified throughout
the execution of the code.
 We have to initialize a constant at the time of
its declaration.
 The compiler can identify constants at the
time of compilation because of the const
keyword.
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Literals
A literal is a static value assigned to variables
and constants
 In C#, there are six types of literals
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Keywords
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Keywords are reserved words and are separately compiled by
the compiler.
They convey a predefined meaning to the compiler and hence
cannot be created or modified.
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Escape sequence characters in
C#
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Console Input/Output Operations
Two output methods: Console.Write() and
Console.WriteLine()
 These two methods accept parameters for
formatting the text before the output is
displayed
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Console.Write(“Customer name: {0}”, custName);
Console.WriteLine(“Total amount: ${0:#,###.#0}”, totalAmount);
Two input methods: Console.Read() and
Console.ReadLine()
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custName = Console.ReadLine();
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Convert Methods
The ReadLine() method can also be used
to accept integer values.
 The data is accepted as string and then
converted into other data type by a
Convert class
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age = Convert.ToInt32(Console.ReadLine());
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Format Specifiers
Format specifiers are special characters
that are used to display values of variables
in a formatted manner.
 Some type of format specifiers
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Number Format Specifiers
Datetime Format Specifiers
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Number Format Specifiers
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We can convert numeric values in different
formats.
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More Number Format Specifiers
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Datetime Format Specifiers
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More Datetime Format Specifiers
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Module 2 – Summary (1)
In C#, data types are also divided into two
categories: value types and reference types
 The predefined data types are referred to as
basic data types in C#.
 C# supports three types of comments
 XML comments are inserted in XML tags.
These tags can either be predefined or userdefined.
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Module 2 – Summary (2)
Two output methods: Console.Write() and
Console.WriteLine()
 Two input methods: Console.Read() and
Console.ReadLine()
 Convert class is used to convert a variable
into another data type.
 Some type of format specifiers: number and
datatime
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