Private Sub btnDisplay_Click(...) Handles btnDisplay.Click
Dim size As Double
size = 435
House(size)
lstOutput.Items.Add("of Representatives")
End Sub
Sub House(ByVal size As Double)
lstOutput.Items.Add(size & " members in the House")
End Sub
2. Determine the output displayed when the button is clicked.
Private Sub btnDisplay_Click(...) Handles btnDisplay.Click
Dim name As String = "Terry Jones"
Abbreviate(name)
txtOutput.Text = name
End Sub
Sub Abbreviate(ByRef a As String)
Dim b As Integer = a.IndexOf("")
a = a.SubString(0, 1) & " . " & a.SubString(b + 1, 1) & "."
End Sub
3. Find the errors.
Private Sub btnDisplay_Click(...) Handles btnDisplay.Click
Dim vowels As Integer 'Number of vowels
ExamineLetter(vowels)
ExamineLetter(vowels)
ExamineLetter(vowels)
txtOutput.Text = "The number of vowels is " & vowels
End Sub
Sub ExamineLetter(ByRef vowels As Integer)
Dim ltr As String
ltr = InputBox("Enter a letter.")
ltr = ltr.ToUpper
If (ltr = "A") Or (ltr = "E") Or (ltr = "I") Or _
(ltr = "O") Or (ltr = "U") Then
vowels += 1
End If
End Sub
(Assume the three responses are U, b, and a.)
4. Rewrite the program so input, processing, and output are each performed by calls to Sub procedures.
Private Sub btnCompute_Click(...) Handles btnCompute.Click
'Convert feet and inches to centimeters
Dim str As String
Dim feet, inches, totalInches, centimeters As Double
str = "Give the length in feet and inches. "
feet = CDbl(InputBox(str & "Enter the number of feet."))
inches = CDbl(InputBox(str & "Enter the number of inches. "))
totalInches = 12 * feet + inches
centimeters = 2.54 * totalInches
txtOutput.Text = "The length in centimeters is " & centimeters
End Sub
5. Determine the output displayed when the button is clicked.
Private Sub btnDetermine_Click(...) Handles btnDetermine.Click
Dim numOne, numTwo, numThree, numLowest As Double
numOne = CDbl(txtOne.Text)
numTwo = CDbl(txtTwo.Text)
numThree = CDbl(txtThree.Text)
numLowest = FindLowest(numOne, numTwo, numThree)
txtLowest.Text = CStr(numLowest)
End Sub
Function FindLowest(ByVal x As Double, ByVal y As Double, _
ByVal z As Double) As Double
'Find the lowest of three numbers denoted by x, y, and z
Dim lowest As Double
lowest = x
If y < lowest Then
lowest = y
End If
If z < lowest Then
lowest = z
End If
Return lowest
End Function
(Assume the first three text boxes contain the numbers 7, 4, and 3.)
6. Determine the output displayed when the button is clicked.
Private Sub btnDisplay_Click(...) Handles btnDisplay.Click
'Determine the day of the week from its number
Dim days As String, num As Integer
days = "SunMonTueWedThuFriSat"
num = CInt(InputBox("Enter the number of the day."))
txtOutput.Text = "The day is " & DayOfWk(days, num) & "."
End Sub
Function DayOfWk(ByVal x As String, ByVal n As Integer) As String
'x String containing 3-letter abbreviations of days
'n The number of the day
Dim position As Integer
position = 3 * n - 3
Return x.Substring(position, 3)
End Function
(Assume the response is 4.)
7. Identify the errors.
Private Sub btnDisplay_Click(...) Handles btnDisplay.Click
Dim word As String
word = InputBox("What is your favorite word?")
txtOutput.Text = "When the word is written twice, " & _
Twice(word) & " letters are used."
End Sub
Function Twice(ByVal w As String) As Integer
'Compute twice the length of a string
Dim len As Integer
Return len = 2 * w.Length