assignment 18.2 new

8/9/2019 Assignment 18.2 NEW

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Assignment 18.2 Software Development (Visual Basic)

The features of a Programming Language

Variables (Naming conventions)

Every piece of date used to make a program must be contained somewhere so that it can belooked back or reused. Programs store this in defined memory called variables. These variablescan be thought of as a temporary source of data. The contents of a variable ends when theprogram is terminated.

The variable could be permanently available when the program is save so all tools used withinthe program will be accessible once closed. A variable have two very important attributeswhich make it unique, a name and a data type. A name is created by the programmer so it willbe easier to establish the variable within the coding of the program.

A data type defines the sort of data a variable can store. Naming conventions for variables areusually expected to have a name with a letter at the beginning and a combination of both lettersand numbers which can consist of a maximum of 255 characters. Symbols are not acceptablewhen naming conventions.

Variables (Local and Global)

Global Variables

A Global variable is a variable that is visible through the whole program and hose value may bemodified by any procedure in the program. So in simpler terms it is a variable that can assessed

throughout a program instead of being restricted to a function.

Local Variables

A Local variable is used and visible only within the body of a procedure or function, and whichretains its value only for the duration of each call to that procedure. Within different procedures, different local variables may be declared with the same name, which eases the task of finding unique names, and avoids a whole class of errors in which a global variable isinadvertently altered by the wrong procedure.

Throughout my program I declared number of different variables some local and some global.Below are samples of code from my program that I created which shows sections that have localvariables.

Public Class FrmNoteSaverDim TheDate As DateTimeDim TheTime As DateTimeDim theResponse As String

Variables declared within a separate module like this are limited to use within that module.When a variable is declared within a class this limits the overall use you have over that variableso you are restricted to most actions. This is what makes this particular section local.


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Loops

Loops are mainly used for iterations so the command that you have stated will be repeateddepending on how many times you have set it to repeat. There are many types of loops howeverthere are only two main ones. These loops are:

Fixed loops - which execute a fixed number of times Conditional Loops This executes the loop repeatedly until some condition is met

Fixed Loops

A Fixed loop like a said before follows a set of instructions as to how many times the programshould repeat itself. If I set the program to repeat itself 10 times, it will loop itself 10 times. Invisual basic these loops are implemented using for statements .

Public Class FrmLoop

Private Sub CmdFor_Click( ByVal sender As System.Object, ByVal e As System.EventArgs)Handles CmdFor.Click

Dim A As IntegerA = 1For A = 1 To 10

MsgBox(A)

Next The code above supports a simple looping program that will independently loop itself 10

times.

For Loop Code

X10


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Continuous Loop

This Loop is similar to a Fixed Loop except there is a condition that needs to be met in order forthe loop to terminate. Throughout Visual Basic these loops are implemented using do LoopUntil statements.

Private Sub CmdDo_Click( ByVal sender As System.Object, ByVal e As System.EventArgs)Handles CmdDo.Click

Dim B As IntegerB = 1Do Until B = 10

MsgBox(B)B = B + 1

LoopEnd Sub

The code above shows how a Do Loop can be written and executed, as you can see thecode is slightly different from the first one hence why they have different names.

Conditional Statements

Conditional statements allow a choice to be made, so the user can execute an event if acertain condition is met within the program. Below is sample code from my program toshow what this means.

Public Class FrmSelection

Private Sub TmrRun_Tick( ByVal sender As System.Object, ByVal e As System.EventArgs)Handles TmrRun.Tick

If CHBOption1.Checked Then

PBBar1.Value = PBBar1.Value + 1

ElseIf CHBOption2.Checked Then

PBBar1.Value = PBBar1.Value - 1

End If

If PBBar1.Value >= 100 ThenTmrRun.Enabled = False

End If

End Sub

Do Loop Code

This is the Coding of the program, so

this is considered very important. Thispart of the section makes the progressgo forward and back. Throughout the

bottom of the coding, that part controlsthe number buttons from 1-4

This code show a conditionalstatement as it basically says that if

you click the Go Forwardcheckbox the progress bar will goforward by 1 and if you click theGo Back checkbox the bar will goback by 1. This is known as aConditional Statement .


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Logical Operators

The conditional statements used in both If and Do Until are familiar with using logical operatorsto combine two or more conditions. Below is a table showing all the logical operators.

Operator Meaning> Greater Than< Less Than= Equal to>= Greater Than or equal to20

AND Gender = M this statement will onlyproduce true if Both elements are true(over 20 and Male)

OR Produces true if either side is true Age>20OR Gender = M this statement willproduce true is EITHER the age is over 20OR the gender is Male

NOT Produces the opposite result NOT(UserInput = Y) this statement will producefalse if the user input is Y, otherwise it willproduce true.

Assignment Statements

Assignment statements in VB are used to assign values to variables. The equals sign attached tothe statement is like an operator and its value is assigned from right to left. The examples belowshows that the value 100 is assigned to my variable which is called Lamar,

Lamar = 100

There are other ways to make combinations with mathematical operators such as,

Lamar = 100 + 25

The will take the original value within the statement and add 25 to it making the new value 125.

The table below show a list of possible mathematical operator you can include in yourassignment statements.

Operator Meaning Examples Order of precedence^ Exponentiation

(raise to the powerof)

2 ^ 3 = 8 1

* Multiplication 3 * 2 = 6 2/ Integer Division 5 / 2 = 2 3Mod Remainder Part of

division5 mod 2 = 1 4

+ Add 4 + 5 = 9 5- Subtract 3 2 = 1 6


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Input and Output Statements

Input and Output Statements are usually completed via controls such as text boxes, list boxes

and buttons which are placed on the form that will be displayed to the user. Below is anexmaple of available controls you can have on a form.

Visual Basic is an event driven programming language, so subroutines are required to bewritten so that it can respond to user events such as clicking a button. The subroutinescollect the value the the user enters in the available text boxes, it then assigns the text property of the text box to a variable. For example:

MyText = txtMyInput.text

The statement assigns the value entered in the a text box called txtMyInput to a variablecalled MyText.

Similarly you can output a value to a text box or label by simply writing the assignment statement in reverse. So the output text label called lblMylabel, the statement would bewritten as,

lblMyLabel.text = Hello

This is a media player which Idevoloped it includes all thenecessary controls with the

use of coding to make itoperational. As you can see Ihave buttons, Labels,menustrips and trackbars . Allof these contols are essentialto make this program work .

LabelButtons

Menustri


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Card Game 21 Program 1 Analysis and Design

This is the 6 th program I created and unlike all the other programs this one is rather enjoyable

because it was made for 2 people and it is based on a popular card game called 21. The mainpurpose of this program is to provide fun and respond to the actions the user presents.

There are a 4 buttons within the program which makes it what it is. As you can see there is a Player 1 and Player 2 Button which is what the user presses to start the game. The New Game buttonrestarts the game so it saves time from closing the whole program and opening it up again. The QuitGame button closes the program.

Structure of the Program

Clicking on the Player 1 Buttoninitiates the game by showingcards in the centre of the

screen. You repeatedly keepon clicking on the player 1until you reach 21. If you get

21 you win the first round, if you get anything other thanthat value you lose.

If you win a RoundIf you lose a Round As both players continue toplay the game they willnotice that the progress bar

will continue to increase.This indicates who iswinning and in the lead.

From the picture above wecan clearly see that player 2is in the lead

The New Game

Button willrestart thegame to save

trouble forclosing andreopening the

program

When a playerwins the game

this messagebox will appear.

In this case

Player 1 Won

the game


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The Coding Of the ProgramThis was the coding used to make the program functional, as you can see it was a long process to

make this game.Public Class Form1

Public P1Cards As Integer = 0

Public P2Cards As Integer = 0

Public P1Score As Integer = 0

Public P2Score As Integer = 0

Private Sub Form1_Load( ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase .Load

End Sub

Private Sub Button1_Click( ByVal sender As System.Object, ByVal e As System.EventArgs)Handles Button1.ClickDim TheRandomClass As New Random

Dim i As Integer = 0

i = TheRandomClass.Next(1, 6)

Label2.Text = i.ToString

P1Cards += i

Label1.Text = "Player 1 Cards: " + P1Cards.ToString

If Label2.Text = 1 Then

PictureBox1.Visible = True

PictureBox2.Visible = False




End If







End If






This section of thecode is programming

when you click on thePlayer 1 button andthe cards switch eachtime


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End If







End If







End If

If P1Cards > 21 Then

MsgBox( "Bust!" , MsgBoxStyle.Critical, "End Of Turn" )

P1Cards = 0

Label2.Text = ""

Label1.Text = "Player 1 Cards: 0"

Button1.Enabled = False

Button2.Enabled = True






End If

If P1Cards = 21 Then

MsgBox( "21!" , MsgBoxStyle.Information, "End Of Turn" )

P1Cards = 0

Label2.Text = ""


Dim o As Integer = 0

o = 1

P1Score += o

Label4.Text = P1Score * 20

ProgressBar1.Value = Label4.Text

This parts programswhen you go over 21 andwhat message will begiven if it happened


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End If

If ProgressBar1.Value = 100 Then

MsgBox( "Player 1 Wins!" , MsgBoxStyle.Information, "End Of Game" )





End IfEnd Sub

Private Sub Button2_Click( ByVal sender As System.Object, ByVal e As System.EventArgs)Handles Button2.Click

Dim TheRandomClass As New Random

Dim i As Integer = 0

i = TheRandomClass.Next(1, 6)

Label2.Text = i.ToString

P2Cards += i

Label5.Text = "Player 2 Cards: " + P2Cards.ToString







End If







End If



This section focuses on

the progress bar andthe action that willoccur when it reaches

100

This section is the exactsame as the first exceptit is focusing on the

player 2 button insteadof player 1.


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End If







End If







End If

If P2Cards > 21 Then

MsgBox( "Bust!" , MsgBoxStyle.Critical, "End Of Turn" )

P2Cards = 0

Label2.Text = ""









End If

If P2Cards = 21 Then

MsgBox( "21!" , MsgBoxStyle.Information, "End Of Turn" )

P2Cards = 0

Label2.Text = ""


Dim o As Integer = 0


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o = 1

P2Score += o

Label7.Text = P2Score * 20

ProgressBar2.Value = Label7.Text








End If

If ProgressBar2.Value = 100 Then

MsgBox( "Player 2 Wins!" , MsgBoxStyle.Information, "End Of Game" )





End IfEnd Sub

Private Sub Button3_Click( ByVal sender As System.Object, ByVal e As System.EventArgs)Handles Button3.Click

P1Cards = 0

P2Cards = 0

P1Score = 0

P2Score = 0



Label2.Text = ""



ProgressBar1.Value = 0

ProgressBar2.Value = 0





PictureBox5.Visible = FalseEnd Sub


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Testing Of the ProgramTest Test Data Use Expected Output Actual Output Test ResultPlayer 1 Button Generate Cards Generated the

CardsPASS

Player 2 Button Generated Cards Generated theCards

PASS

New GameButton

Restart the Game Restarted theGame

PASS

Quit GameButton

Close The Game Closed The Game PASS

Technique/Tool Justification Witness Statement Picture Box This tool helps to display the pictures

before. The cards are all implementedby using this tool

This tool helped incredibly well with program because it displayed all the necessary cards once inplay. Without this key tool my program would be inactive and faulty.


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Program Selection Method Analysis and Desi gn

This was the 4 th program I created; it took very little time to create it as the amount of buttons and

functions I had installed was the very minimum. The main purpose of this program is the response tothe clicking of a button and returns an event. Also the click of either of the options should make theprogress bar gradually increase or decrease. In my opinion this program isnt as important as thebrowser because it doesnt serve any real purpose towards the public. It is simply used for thetesting of different buttons and functions.

This is what the program looks like; it is a simple but manageable program. The background of theprogram makes it look more presentable a sleek. Like I

said before there are 6 buttons you can click from andeach one of them gives a different response, especiallythe Go forward and Go Back buttons. Button 1,2,3,4

presents a message box telling the viewers what he justdid. In the next part of this report you will see what I

mean.

Clicking on the Go Forward option allows the progressbar to go forward slowlybut surely.

Clicking on the Go Backoption allows the progress

bar to go back slowly butsurely


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Structure of the Program

Test TestDataused

ExpectedOutput

ActualOutput

TestResult

GoForwardCheck Box

ProgressBar ShouldGoForward

ProgressBar wentforward

PASS

Go Back

Check Box

Progress

Bar ShouldReverse

Progress

BarReversed

PASS

Button 1 Shows aMessageBox

Showed aMessageBox

PASS


Showed aMessageBox

PASS


Showed aMessageBox

PASS

Button 4 Shows aMessage

Showed aMessage

PASS

Clicking on the Go

Forward ButtonClicking on the

Go Back Button

Clicking on

Button 1

Clicking on

Button 2

Clicking on

Button 3

Clicking on

Button 4


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Technique/Tool Justification Witness StatementCheckbox The reason for this tool is give

the user selection choices. If he/she does select the GoForward he/she can select theGo back button as well.

Progress Bar This is used to show theprogress of the event

Buttons I have used the button toinitiate a click event.

The properties

show thecharacteristics anddetails of the

program. Soeverything on theprogram looks the

way it is becauseof its properties.

Within this program I used the checkbox tool, button tool and a progress bar. Both these tools arevery helpful and actually made the program what it is. With these too tools the program would havelacked stability. The button tool was coded to initiate an event.

assignment 18.2 new

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