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Today’s Menu:

Loops

Assignment 4

Get data with input box, assign it to a variable, put it to textbox, calculate, and loop back.

From now on we are going to be using buttons.

Look at the program on pg113. This program calculates overtime pay.
Hint: whenever you write a program, do not use a loop. Do it without a loop to see if it works for one instance.

· Make a form with a button called compute overtime pay.

· Double click on that and then program it.

· We need declaration of variables.
Hint: anything regarding money should be declared as Double.

· We are going to use 3 inputbox values.

· We need to calculate overtime hours, after that we need to find regular pay.

Display all data into textboxs.

Dim empID, hoursworked, overtimehours As Integer

Dim hourlyrate, overtimepay, regularpay, grosspay As Single

empID = InputBox("ENTER EMPLOYEE ID")

TextBox1.Text = empID

hoursworked = InputBox("ENTER HOURS WORKED")

TextBox2.Text = hoursworked

hourlyrate = InputBox("ENTER HOURLY RATE")

TextBox3.Text = hourlyrate

If (hoursworked > 40) Then

overtimehours = hoursworked - 40

overtimepay = overtimehours * hourlyrate * 1.5

regularpay = 40 * hourlyrate

Else

overtimehours = 0

overtimepay = 0

regularpay = hoursworked * hourlyrate

End If

grosspay = regularpay + overtimepay

Textbox4.text = overtimehours

Textbox5.text = overtimepay

Textbox6.text = regularpay

Textbox7.text = grosspay

Textbox5.text = formatcurrency(overtimepay)

Textbox6.text = formatcurrency(regularpay)

Textbox7.text =formatcurrency(grosspay)

HINT: This extra code clears all button.
TextBox1.Text = ""

TextBox2.Text = ""

TextBox3.Text = ""

TextBox4.Text = ""

TextBox5.Text = ""

TextBox6.Text = ""

TextBox7.Text = ""

Let’s do it 2 times using a loop. (While)
NOTE: We only pasted while code!

Dim empID, hoursworked, overtimehours, n As Integer

Dim hourlyrate, overtimepay, regularpay, grosspay As Single

n = 0

While (n < 3)

empID = InputBox("ENTER EMPLOYEE ID")

TextBox1.Text = empID

hoursworked = InputBox("ENTER HOURS WORKED")

TextBox2.Text = hoursworked

hourlyrate = InputBox("ENTER HOURLY RATE")

TextBox3.Text = hourlyrate

If (hoursworked > 40) Then

overtimehours = hoursworked - 40

overtimepay = overtimehours * hourlyrate * 1.5

regularpay = 40 * hourlyrate

Else

overtimehours = 0

overtimepay = 0

regularpay = hoursworked * hourlyrate

End If

grosspay = regularpay + overtimepay

TextBox4.Text = overtimehours

TextBox5.Text = FormatCurrency(overtimepay)

TextBox6.Text = FormatCurrency(regularpay)

TextBox7.Text = FormatCurrency(grosspay)

n = n + 1

End While

Now, let’s take the inputbox out

There is a problem when using textbox and the loop. That’s why we are trying to use inputbox.

Dim empID, hoursworked, overtimehours, n As Integer

Dim hourlyrate, overtimepay, regularpay, grosspay As Single

n = 0

While (n < 3)

empID = TextBox1.Text

hoursworked = TextBox2.Text

hourlyrate = TextBox3.Text

If (hoursworked > 40) Then

overtimehours = hoursworked - 40

overtimepay = overtimehours * hourlyrate * 1.5

regularpay = 40 * hourlyrate

Else

overtimehours = 0

overtimepay = 0

regularpay = hoursworked * hourlyrate

End If

grosspay = regularpay + overtimepay

TextBox4.Text = overtimehours

TextBox5.Text = FormatCurrency(overtimepay)

TextBox6.Text = FormatCurrency(regularpay)

TextBox7.Text = FormatCurrency(grosspay)

n = n + 1

MsgBox(n)

End While

This is a sample of the test from previous semesters.

Visual Basic .Net True / False Dr. Ebrahimi

Name__________________________________

T / F 1) A systematic way or step by step procedure to solve problem is known as an algorithm.

T / F 2) A program is a set of instructions that tell a computer what to do.

T / F 3) Every character languages has its own ASCII code, such as 65 for uppercase A and 97 for lowercase a.

T / F 4) Computer languages are ambiguous and natural languages are not ambiguous.

T / F 5) Visual Basic. Net was developed before Visual Basic and Basic.

T / F 6) The input shown on the screen can be printed using the print command.

T / F 7) Every problem has only one algorithm to solve it.

T / F 8) Human intervention is required to review logical statements, because the compiler will not catch logical errors.

T / F 9) In order to get an output from a program you must edit, compile, and execute the program.

T / F 10) Dim fin As IO.StreamReader = IO.File.OpenText("*.txt") will read the data from all text files in your program's bin folder.

T / F 11) You can still execute a program even if there is a warning.

T / F 12) In Visual Basic .Net, an “ If …Then…Else” statement is used to create a loop.

T / F 13) A # is used to comment a line of text in vb.

T / F 14) Basic, Visual Basic, C, C++, Visual Basic .Net, Java, and C# are all visual programming languages.

T / F 15) The binary state of a computer is represented as 0 and 1 at the lowest level.

T / F 16) With the symbol ‘ you can create a single line of comment.

T / F 17) Basic is better than Visual Basic and Visual Basic.net because it is simple object oriented.

T / F 18) Visual basic.net is an object oriented software.

T / F 19) Visual Basic was developed before Basic and Visual Basic.net.

T / F 20) Visual Basic and Visual Basic.net are user Friendly and were designed for teaching purposes only.

T / F 21) A Visual Basic program has the extension .vb and a form in the program uses the extension .frm.

T / F 22) The ToolBox is usable when editing your code in the form view and design view.

T / F 23) Basic was line oriented therefore to execute multiple statements you must use goto.

T / F 24) Basic was designed by two professors John Kennedy and Thomas Krutz from Dartmouth College.

T / F 25) HoursWorked=Msgbox(“Enter the Employee Id”) is a logically correct statement

T / F 26) One way to make a decision in a program is to use an If statement.

T / F 27) To find the maximum of two numbers, the following If statement can be used:

If a = b Then

max = a

Else

max = b

End If

T / F 28) The following will set different a tax rate depending on gross pay:

If grosspay > 500 Then

taxrate = 0.20

Else

taxrate = 0.05

End If

T / F 29) Overtime pay can be computed using the following:

If hoursworked > 40 Then

overtimehours = hoursworked - 40

Else

overtimehours = 0

grosspay = hoursworked * hourlyrate + overtimehours

T / F 30) This validation can be used to make sure gross pay is a positive value:

If grosspay > 0 Then

MsgBox(grosspay)

Else

MsgBox(“Error in gross pay”)

End If

T / F 31) An If statement that contains other If statements as part of its body is called a nested If.

T / F 32) Every Else in a program must correspond to an If statement.

T / F 33) Both a and b need to be True for “Hello” to be displayed:

If a Or b Then MsgBox(“Hello”)

T / F 34) The following statement is always True: True And False.

T / F 35) There is a logical error in the following:

If number > max Then

max = number

Else min = number

T / F 36) User interaction, comparison with stored data, and response are components of a search program.

T / F 37) The following statement is logically correct:

If hoursworked > 40 Then

overtimehours = hoursworked – 40

Else

overtimehours = 0

End if

T /F 38) The following statement can be used to verify that a number has been entered for hours worked before using it to compute gross pay:

If TextBox1.Text = “” Then

Msgbox(“ENTER A VALUE FOR HOURS WORKED”)

TextBox1.SetFocus

Else

TextBox3.Text = TextBox1.Text * TextBox2.Text

End If

T / F 39) Net pay is needed in order to calculate the tax amount.

T / F 40) CheckBox can be used when only one entry can be selected, for example, marital status or credit card.

T / F 41) When you have to choose two or more options among many, you have to use RadioButtons. For examples, health insurance likes full coverage, dental etc.

T / F 42) The following statements will assign an employee with a gross pay of 0 a tax rate of 20%:

If grosspay > 500 Then

taxrate = 0.20

ElseIf grosspay > 300 Then

taxrate = 0.15

Else

taxrate = 0.10

End If

T / F 43) The keyword And represents a logical operator that can be used in a condition for an If statement.

T / F 44) The keyword Or represents a logical operator that when used in a condition, the condition will be True only when both expressions are True.

T / F 45) In a sequential file system, often a large portion of the file must be read in order to find one specific item.

T / F 46) While counter is the same as While counter > 0.

T / F 47) In order to work with a file in your program you must open and indicate what you want to do with the file.

T / F 48) To sum a series of numbers you need to initialize the sum = 1.

T / F 49) The following loop will read all employeeid from a file one by one.

While myfile.Peek <> -1

employeeid = myfile.ReadLine

End While

T / F 50) The following loop will compute the gross pay for 20 employees:

For i = 0 To 20

grosspay= InputBox(“Enter hours worked: “)

Next

T / F 51) The values 5 and 6 will be displayed:

Dim x As Integer

x = 5

x = 6

MsgBox(x)

T / F 52) In Visual Basic, the expression 2 < 3 always evaluates to true, and 0 is always false.

T / F 53) The statement While 1 … End While in a program will loop forever.

T / F 54) Reserved words While, For, and Do While can be used to loop.

T / F 55) The Not operator means negation.

T / F 56) The assignment statement c = c + 1 is same as c += 1.

T / F 57) To loop five times we need: Dim counter As Integer While counter >5 counter = counter + 1 End While.

T / F 58) When using end of file it is necessary to stop the loop by a counter variable in a loop condition.

T / F 59) To loop a program 5 times, you must write the program 5 times.

T / F 60) To run a program with a large amount of data it is better to enter the data each time interactively.

T / F 61) Every time you recompile a program you must also recompile its data file.

T / F 62) If there are no errors detected by the compiler, the program output is correct.

T / F 63) The declaration: Dim employeeid Integer is correct.
T / F 64) A dummy value that is used to stop a loop is known as a sentinel.

T / F 65) A loop can have one or more statements enclosed in braces, or a single statement without braces.

T / F 66) When the condition of a loop becomes false, the execution continues at the statement after the loop.

T / F 67) The While loop is more compact than For loop, since it keeps the loop control statements together.

T / F 68) The position of braces in a loop is very important and you can’t choose your own style.

T / F 69) BASIC means Beginners‘ All-purpose Symbolic Instruction Code.

T / F 70) Visual Basic is a high level programming language evoloved from the earlier DOS version called BASIC.

T / F 71) By visualization, it means that Visual Basic will display the execution of program visually.

T / F 72) The following statement adds the two values in the textboxes:

TextBox3.Text = TextBox2.Text + TextBox1.Text

T / F 73) The following is a valid Visual Basic statement:

Dim tax rate As Single

Tax rate = TextBox1.Text

T / F 74) If you don’t change the name for the controls all the name are defaulted with a number for example Text1 instead of hours worked.

T / F 75) When you start the VB environment, you are in the design mode rather than run mode.

T / F 76) You can change the name of a control in the Text property.

T / F 77) It is a Visual Basic convention to name a control with a shorthand prefix such as txthoursworked, 1b1hoursworked, btncomputenetpay.

T / F 78) The following statement is logically correct:

If hour>40 Then

Overtimehour = hour – 40

Else

Overtimehour = 10

End if

T / F 79) The following statement doesn’t compute grosspay when there is a blank in the textbox:

If textbox1.text = “” then

Msgbox(“ENTER A VALUE”)

Textbox1.setfocus

If text

Else

Textbox3.text = textbox1.text*textbox2.text

T / F 80) Every control can be programmed. For example a TextBox can be programmed.

T / F 81) TextBox1.TextChanged will activate when you click the command button.

T / F 82) By using buttons or textboxes with the labels you can design interfaces such as telephone or calculators.

T / F 83) You can’t use code to change properties of any controls, for example

Textbox .text .visible = true, or text1.forecolor = color.green

T / F 84) Visual basic is not a event-driven programming language, it is a procedural language. For example, each control such as botton 1_ click() or botton2_doubleclick()

T / F 85) Text box can only be use for input as well as output.

T / F 86) It is not possible to compute the gross pay by simply re-entering the hourly rate.

T / F 87) In order to calculate overtime we need to know hourly rate in the textbox2

T / F 88) it is a good style to choose proper size for person name, hours works, and hourly rate in the labels and text boxes

T / F 89) Check box can be use when there is only one entry must be selected, for example, marital status or credit cards

T / F 90) when you have to choose two or more options among many, you have to use radio buttons. For examples, health insurance likes full coverage, dental etc.

T / F 91) radio buttons must be grouped in a frame

T / F 92) the following are nested if statement:

If grosspay>500 then taxrate=0.20

If grosspay >300 then taxrate=0.15

if grosspay<=300 then taxrate=.10

T / F 93) the following if statement has the same taxrate as above

If grosspay>500 then

Taxrate=0.20

Elseif grosspay>300 then

taxrate=0.15

else

taxrate=0.10

end if

T / F 94) the following statement will clear and end the program

textbox1.text=”“

End

End sub

T / F 95) dim is stand for dimension and it is used declare variables of integer, single, double, string. For example

T / F 96) the following statement indicates the variable netpay is a whole number instead of fraction

Dimension netpay as single

T / F 97) the following one is valid:

If textbox1.text=”ebrahimi” then

Msgbox(“your salary is” , netpay)

end if

T / F 98) Both a and b need to be True for “Help” to be displayed:

If a Or b Then MsgBox(“Help”)

T / F 99) The key word Or represent a logical operation that can be use by separate nested if statement.

T / F 100) the following is not a valid statement:

If radio1.checked = true Then

checkbox.checked= true