01 Iec t1s1 Oops Session 01
Transcript of 01 Iec t1s1 Oops Session 01
-
8/14/2019 01 Iec t1s1 Oops Session 01
1/45
-
8/14/2019 01 Iec t1s1 Oops Session 01
2/45
Slide 2 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
In this session, you will learn to:
Explain features of the object-oriented methodology
Describe the phases of the object-oriented methodology
Define classes in C#
Declare variablesWrite and execute C# programs
Objectives
-
8/14/2019 01 Iec t1s1 Oops Session 01
3/45
Slide 3 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
Object orientation is a software development methodology
that is based on modeling a real-world system.
An object oriented program consists of classes and objects.
Let us understand the termsclass and objects
Object-Oriented Methodology
-
8/14/2019 01 Iec t1s1 Oops Session 01
4/45
Slide 4 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
Toyota CamrySuzuki Reno Honda Acura
Objects
Class
Object-Oriented Methodology (Contd.)
Car
-
8/14/2019 01 Iec t1s1 Oops Session 01
5/45
Slide 5 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
An object means a material thing that is capable of being
presented to the senses.
An object has the following characteristics:
It has a state
It may display behaviorIt has a unique identity
Objects interact with other objects through messages.
Let us understand these concepts.
The Foundation of Object Orientation
-
8/14/2019 01 Iec t1s1 Oops Session 01
6/45
Slide 6 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
Car positioned at one place defines its State
Movement of car defines its Behavior
Car number XX 4C 4546 shows
the Identity of the car
The Foundation of Object Orientation (Contd.)
-
8/14/2019 01 Iec t1s1 Oops Session 01
7/45Slide 7 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
Car is flashing the lights to pass
the message to the other car
The Foundation of Object Orientation (Contd.)
-
8/14/2019 01 Iec t1s1 Oops Session 01
8/45Slide 8 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
Just a minute
Identify the possible states of the following objects:
1. A cell phone
2. A stereo
Solution:1. States of a cell phone: Off, Ring, Vibrate, and Call
2. States of a stereo: Play, Pause, Rewind, and Forward
-
8/14/2019 01 Iec t1s1 Oops Session 01
9/45Slide 9 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
Just a minute
Dr. James and Mr. Hyde went to the railway station to book
tickets for 3rd December. At the railway station, they requested
the clerk at the ticket counter to book two tickets for the Flying
Express in the first class. Identify the following:
1. The possible receiver of the message in this situation.
2. The possible method that the receiver can use.
Solution:
1. The receiver of the message in this case will be the clerk at
the ticket counter.2. The clerk will check if two tickets are available on the
requested train in the desired class and for the desired date. If
the tickets are available, the clerk will enter the details (name,
age, departure date, and seat), confirm the reservation, and
collect the required fare.
-
8/14/2019 01 Iec t1s1 Oops Session 01
10/45Slide 10 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
Characteristics of the Object-Oriented Approach
Realistic modeling
Reusability
Resilience to change
Existence as different forms
-
8/14/2019 01 Iec t1s1 Oops Session 01
11/45Slide 11 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
Just a minute
State whether the following situations demonstrate
reusability:
1. Recycling paper
2. Pump reusability (same pump is used in a well and in a fuel
station)
Solution:
1. It does not represent reusability because the unusable paper
is destroyed before paper is recycled for use. The unusable
paper loses its identity and cannot be considered the same as
recycled paper.2. It represents reusability because a pump can be used for
suction of water as well as petrol. It is not necessary to use
the same pump in both the cases. Two separate machines
can be used because both belong to the Pump class.
-
8/14/2019 01 Iec t1s1 Oops Session 01
12/45Slide 12 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
The following phases are involved in the software
development:
The Analysis phase
The Design phase
The Implementation phase
Let us discuss the process of constructing a building.
Phases of Object Orientation
-
8/14/2019 01 Iec t1s1 Oops Session 01
13/45Slide 13 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
Just a minute
As a member of a team that is developing software for
DialCom Telecommunications, Inc., you have been
assigned the task of creating a software module that
accepts and displays customer details such as name, age,
and phone number. Identify the class that you will create
and the methods of the class.
Solution:
As per the problem statement, the class required is:
Customer
The class should have the methods to:
Accept customer details
Display customer details
-
8/14/2019 01 Iec t1s1 Oops Session 01
14/45Slide 14 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
A program is a set of instructions to perform a specific task.
Programming languages use programs to develop software
applications.
A compiler is a special program that processes the
statements written in a particular programming languageand converts them into a machine language.
This process of conversion is called compilation.
Introducing C#
-
8/14/2019 01 Iec t1s1 Oops Session 01
15/45Slide 15 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
C#, also known as C-Sharp, is a programming language
introduced by Microsoft.
C# is specially designed to work with the Microsofts .NET
platform.
Let us understand the structure of a C# program.
Introducing C# (Contd.)
-
8/14/2019 01 Iec t1s1 Oops Session 01
16/45Slide 16 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
Consider the following code example, which defines a class:
public class Hello
{
public static void Main(string[] args)
{System.Console.WriteLine("Hello, World!
\n");
}
}
Classes in C#
-
8/14/2019 01 Iec t1s1 Oops Session 01
17/45Slide 17 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
public class Hello
{
public static void
Main(string[] args)
{
System.Console.WriteLine("He
llo, World! \n");
}
}
Classes in C# (Contd.)
The class Keyword
Is used to declare a
class
-
8/14/2019 01 Iec t1s1 Oops Session 01
18/45Slide 18 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
public class Hello
{
public static void
Main(string[] args)
{
System.Console.WriteLine("He
llo, World! \n");
}
}
The class Name
Is used as an identifier
for a class
Classes in C# (Contd.)
-
8/14/2019 01 Iec t1s1 Oops Session 01
19/45Slide 19 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
public class Hello
{
public static void
Main(string[] args)
{
System.Console.WriteLine("He
llo, World! \n");
}
}
The Main() Function
Is the entry point of an
application
Is used to create
objects and invokemember functions
Classes in C# (Contd.)
-
8/14/2019 01 Iec t1s1 Oops Session 01
20/45Slide 20 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
public class Hello
{
public static void
Main(string[] args)
{
System.Console.WriteLine("He
llo, World! \n");
}
}
System.Console.WriteLine()
Displays the enclosed text on
the screen
Classes in C# (Contd.)
-
8/14/2019 01 Iec t1s1 Oops Session 01
21/45Slide 21 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
public class Hello
{
public static void
Main(string[] args)
{
System.Console.WriteLine("He
llo, World! \n");
}
}
The Escape Character
Displays New line
character. Other special
characters can also be
displayed such as \t, \b
and \r
Classes in C# (Contd.)
-
8/14/2019 01 Iec t1s1 Oops Session 01
22/45Slide 22 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
Demo: Creating Classes
Problem Statement:
As a member of a team that is developing toys for JoyToys,
Inc., you have been assigned the task of creating a bike
module that accepts and displays bike details. Declare the Bike
class and its member functions. The member function that
accepts bike details should display the message AcceptingBike Details. Similarly, the member function to display bike
details on the screen should display the message Displaying
Bike Details.
-
8/14/2019 01 Iec t1s1 Oops Session 01
23/45
Slide 23 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
A variable is a location in the memory that has a name and
contains a value.
A variable is associated with a data type that defines the
type of data that can be stored in a variable.
Declaring Variables
-
8/14/2019 01 Iec t1s1 Oops Session 01
24/45
Slide 24 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
You can declare and initialize variables by using the
following syntax:
=;
Declaring and Initializing Variables
-
8/14/2019 01 Iec t1s1 Oops Session 01
25/45
Slide 25 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
Consider the followingexample of declaring andinitializing a variable:
int class_rank=2;
Declaring and Initializing Variables (Contd.)
Data Types in C#
Represents the kind of
data stored in a variable
C# provides you with
various built-in datatypes, such as:
char
int
float
double
bool
string
-
8/14/2019 01 Iec t1s1 Oops Session 01
26/45
Slide 26 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
Data Types in C#
Let us now understand the various data types with the help
of examples.
-
8/14/2019 01 Iec t1s1 Oops Session 01
27/45
Slide 27 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
Name
Marks
Age
Vowel
string
float
int
char
= Peter
= 83.56
= 23
= a
Data Types in C# (Contd.)
-
8/14/2019 01 Iec t1s1 Oops Session 01
28/45
Slide 28 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
Consider the following
example of declaring and
initializing a variable:
int class_rank=2;
Data types in C#
The following types of
data types are supported
by C#:
Value types
Num
Memory allocated
Variable declared and Initialized
int Num;
Num=5; 5
Data Types in C# (Contd.)
Memory Allocation in Value Type
-
8/14/2019 01 Iec t1s1 Oops Session 01
29/45
Slide 29 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
Consider the following
example of declaring and
initializing a variable:
int class_rank=2;
Declaring and Initializing Variables
Data types in C#
The following types of
data types are supported
by C#:
Reference types
string Str=Hello;
Str
0 1 2 3 4
H E L L O
Address
Memory Allocation of the String Type Variable
-
8/14/2019 01 Iec t1s1 Oops Session 01
30/45
Slide 30 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
Consider the following
example of declaring and
initializing a variable:
int class_rank=2;
Declaring and Initializing Variables (Contd.)
Naming variables in C#
The following rules are used
for naming variables in C#:
Must begin with a letter or
an underscore Should not contain any
embedded spaces or
symbols
Must be unique
Can have any number ofcharacters
Keywords cannot be used
as variable names
-
8/14/2019 01 Iec t1s1 Oops Session 01
31/45
Slide 31 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
Consider the following
example of declaring and
initializing a variable:
int class_rank=2;
Declaring and Initializing Variables (Contd.)
Examples and non-examples
of Naming Variables
Name
#Score
Age
2Strank
Family_Size
Gender
-
8/14/2019 01 Iec t1s1 Oops Session 01
32/45
Slide 32 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
Consider the
following example of
declaring and
initializing a variable:
int class_rank=2;
Declaring and Initializing Variables (Contd.)
Initializing Variables in C#
Specifies the value that
needs to be stored in a
variable. The value could be
an integer, a decimal, or a
character.
-
8/14/2019 01 Iec t1s1 Oops Session 01
33/45
Slide 33 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
To understand how to accept
value in a variable, let us
consider the following code
snippet:
int Number;
Number=
Convert.ToInt32(Console.Rea
dLine());
Accepting and Storing Values in Member Variables
Console.ReadLine()
Is used to accept input
from the user and store it
in the variable
-
8/14/2019 01 Iec t1s1 Oops Session 01
34/45
Slide 34 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
To understand how to accept
value in a variable, let us
consider the following code
snippet:
int Number;
Number=
Convert.ToInt32(Console.Rea
dLine());
Accepting and Storing Values in Member Variables(Contd.)
Convert.ToInt32()
Converts the value
entered by the user to
the int data type
Obj O i d i i C
-
8/14/2019 01 Iec t1s1 Oops Session 01
35/45
Slide 35 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
Let us know learn to write, compile, and execute a C#
program.
Writing and Executing a C# Program
Obj O i d P i U i C#
-
8/14/2019 01 Iec t1s1 Oops Session 01
36/45
Slide 36 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
A C# program can be written by using an editor like
Notepad. Consider the following code, which declares a
class Car and also creates an object MyCar of the same
class:
using System;
class Car
{
//Member variables
string Engine;
int NoOfWheels;
//Member functionsvoid AcceptDetails()
Creating a Sample C# Program
The using keyword is used to include
the namespaces in the program.
Comments are used to explain the
code and are represented by //
symbols.
Member variables are used to store
the data for a class.
Member functions are declared insidethe class that are used to perform a
specific task.
Obj t O i t d P i U i C#
-
8/14/2019 01 Iec t1s1 Oops Session 01
37/45
Slide 37 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
{
Console.WriteLine("Enter the Engine Model");
Engine = Console.ReadLine();
Console.WriteLine("Enter the number of Wheels");
NoOfWheels = Convert.ToInt32(Console.ReadLine());
}public void DisplayDetails()
{
Console.WriteLine("The Engine Model is:{0}",
Engine);
Console.WriteLine("The number of wheels are:{0}",
NoOfWheels);
}
}
Creating a Sample C# Program (Contd.)
Obj t O i t d P i U i C#
-
8/14/2019 01 Iec t1s1 Oops Session 01
38/45
Slide 38 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
//Class used to instantiate the Car class
class ExecuteClass
{
public static void Main(string[] args)
{
Car MyCar = new Car();MyCar.AcceptDetails();
MyCar.DisplayDetails();
}
}
Creating a Sample C# Program (Contd.)
The Execute class is used as a class from
where the Car class can be instantiated.
Obj t O i t d P i U i C#
-
8/14/2019 01 Iec t1s1 Oops Session 01
39/45
Slide 39 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
After writing the program in a Notepad, you need to compile
and execute it to get the desired output.
The compiler converts the source code that you write into
the machine code, which the computer can understand.
The following steps are needed to compile and execute aC# program.
1. Save the code written in the Notepad with an extension .cs.
2. To compile the code, you need to go to the Visual Studio
2005Command Prompt window. Select StartAllProgramsMicrosoft Visual Studio 2005Visual StudioToolsVisual Studio 2005 Command Prompt. The VisualStudio 2005 Command Prompt window is displayed to
compile the program.
3. In the Visual Studio 2005 Command Prompt window, move
to the location where the programs file is saved.
Compiling and Executing C# Program
Obj t O i t d P i U i C#
-
8/14/2019 01 Iec t1s1 Oops Session 01
40/45
Slide 40 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
4. Compile the program file by using the following command:
csc ExecuteClass.cs
5. To execute the code, type the following in the command
prompt:
ExecuteClass.exe
Compiling and Executing C# Program (Contd.)
Obj t O i t d P i U i C#
-
8/14/2019 01 Iec t1s1 Oops Session 01
41/45
Slide 41 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
Problem Statement:
David is the member of a team that is developing the
Automatic Ranking software for a tennis tournament. You have
been assigned the task of creating a program. The program
should accept the following details of a tennis player and
display it:Name, containing a maximum of 25 characters
Rank as an integer
Winning average as a decimal value
Help David to create the program.
Demo: Creating a C# Program
Object Oriented Programming Using C#
-
8/14/2019 01 Iec t1s1 Oops Session 01
42/45
Slide 42 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
In this session, you learned that:
According to the object-oriented approach, systems consist of
component objects that interact with each other.
An object is an entity that may have a physical boundary.
However, it should have the following characteristics:
State
Behavior
Identity
A class consists of a set of objects that share a common
structure and behavior.
If an object desires an action from another object, it sends amessage to that object.
The object that receives the message is called the receiver, and
the set of actions taken by the receiver constitutes the method.
Summary
Object Oriented Programming Using C#
-
8/14/2019 01 Iec t1s1 Oops Session 01
43/45
Slide 43 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
The features of the object-oriented approach are:
Realistic modeling
Reusability
Resilience to change
Existence as different forms
A model of a system is built in the stages of analysis, designand implementation.
The purpose of the model is to help developers understand the
reality that they are trying to imitate.
In C#, a class is created by using the keyword class. It is
identified by a name called the class name.The Console.WriteLine() method is used to display text on the
screen.
Main() is the first function which is executed in a C# program.
Summary (Contd.)
Object Oriented Programming Using C#
-
8/14/2019 01 Iec t1s1 Oops Session 01
44/45
Slide 44 of 45Session 1Ver. 1.0
Object-Oriented Programming Using C#
Escape characters are used to display special characters such
as the newline character.
A variable is a named location in the memory, which contains a
specific value.
A datatype defines the type of data that can be stored in a
variable.The two types of data type are Value type and Reference type.
The ReadLine() method is used to accept inputs from the
user.
The using keyword is used to include the namespaces in the
program.A namespace contains a set of related classes.
Member variables are declared inside the class body.
Summary (Contd.)
Object Oriented Programming Using C#
-
8/14/2019 01 Iec t1s1 Oops Session 01
45/45
Object-Oriented Programming Using C#
Comment entries are notes written by a programmer in the
code so that others reading that code can understand it better.
An object is an instance of a class.
The compiler software translates a program written in a
language like C# into the machine language.
Summary (Contd.)