Option Strict On
Public Class frmMain
    Inherits System.Windows.Forms.Form

#Region " Windows Form Designer generated code "

    Public Sub New()
        MyBase.New()

        'This call is required by the Windows Form Designer.
        InitializeComponent()

        'Add any initialization after the InitializeComponent() call

    End Sub

    'Form overrides dispose to clean up the component list.
    Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
        If disposing Then
            If Not (components Is Nothing) Then
                components.Dispose()
            End If
        End If
        MyBase.Dispose(disposing)
    End Sub

    'Required by the Windows Form Designer
    Private components As System.ComponentModel.IContainer

    'NOTE: The following procedure is required by the Windows Form Designer
    'It can be modified using the Windows Form Designer.  
    'Do not modify it using the code editor.
    Friend WithEvents Label1 As System.Windows.Forms.Label
    Friend WithEvents Label2 As System.Windows.Forms.Label
    Friend WithEvents txtHeight As System.Windows.Forms.TextBox
    Friend WithEvents Label3 As System.Windows.Forms.Label
    Friend WithEvents txtWidth As System.Windows.Forms.TextBox
    Friend WithEvents txtOutput As System.Windows.Forms.TextBox
    Friend WithEvents btnCompute As System.Windows.Forms.Button
    Friend WithEvents btnExit As System.Windows.Forms.Button
    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
        Me.Label1 = New System.Windows.Forms.Label()
        Me.Label2 = New System.Windows.Forms.Label()
        Me.txtHeight = New System.Windows.Forms.TextBox()
        Me.Label3 = New System.Windows.Forms.Label()
        Me.txtWidth = New System.Windows.Forms.TextBox()
        Me.txtOutput = New System.Windows.Forms.TextBox()
        Me.btnCompute = New System.Windows.Forms.Button()
        Me.btnExit = New System.Windows.Forms.Button()
        Me.SuspendLayout()
        '
        'Label1
        '
        Me.Label1.Location = New System.Drawing.Point(24, 16)
        Me.Label1.Name = "Label1"
        Me.Label1.Size = New System.Drawing.Size(256, 16)
        Me.Label1.TabIndex = 0
        Me.Label1.Text = "Enter the lengths of the sides of your rectangle."
        '
        'Label2
        '
        Me.Label2.Location = New System.Drawing.Point(24, 48)
        Me.Label2.Name = "Label2"
        Me.Label2.Size = New System.Drawing.Size(40, 16)
        Me.Label2.TabIndex = 1
        Me.Label2.Text = "Height"
        '
        'txtHeight
        '
        Me.txtHeight.Location = New System.Drawing.Point(80, 48)
        Me.txtHeight.Name = "txtHeight"
        Me.txtHeight.Size = New System.Drawing.Size(64, 20)
        Me.txtHeight.TabIndex = 2
        Me.txtHeight.Text = ""
        '
        'Label3
        '
        Me.Label3.Location = New System.Drawing.Point(24, 72)
        Me.Label3.Name = "Label3"
        Me.Label3.Size = New System.Drawing.Size(40, 24)
        Me.Label3.TabIndex = 3
        Me.Label3.Text = "Width"
        '
        'txtWidth
        '
        Me.txtWidth.Location = New System.Drawing.Point(80, 72)
        Me.txtWidth.Name = "txtWidth"
        Me.txtWidth.Size = New System.Drawing.Size(64, 20)
        Me.txtWidth.TabIndex = 4
        Me.txtWidth.Text = ""
        '
        'txtOutput
        '
        Me.txtOutput.Location = New System.Drawing.Point(16, 120)
        Me.txtOutput.Multiline = True
        Me.txtOutput.Name = "txtOutput"
        Me.txtOutput.ReadOnly = True
        Me.txtOutput.Size = New System.Drawing.Size(256, 128)
        Me.txtOutput.TabIndex = 5
        Me.txtOutput.Text = ""
        '
        'btnCompute
        '
        Me.btnCompute.Location = New System.Drawing.Point(192, 48)
        Me.btnCompute.Name = "btnCompute"
        Me.btnCompute.Size = New System.Drawing.Size(80, 48)
        Me.btnCompute.TabIndex = 6
        Me.btnCompute.Text = "&Compute"
        '
        'btnExit
        '
        Me.btnExit.Location = New System.Drawing.Point(24, 256)
        Me.btnExit.Name = "btnExit"
        Me.btnExit.Size = New System.Drawing.Size(248, 24)
        Me.btnExit.TabIndex = 7
        Me.btnExit.Text = "E&xit"
        '
        'frmMain
        '
        Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
        Me.ClientSize = New System.Drawing.Size(292, 285)
        Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.btnExit, Me.btnCompute, Me.txtOutput, Me.txtWidth, Me.Label3, Me.txtHeight, Me.Label2, Me.Label1})
        Me.Name = "frmMain"
        Me.Text = "Function Demo"
        Me.ResumeLayout(False)

    End Sub

#End Region
    Function GetNumber(ByRef txtBox As TextBox) As Single
        '**********************************************************************************************************
        ' The purpose of this function is to return a single precision value from a text box.
        '**********************************************************************************************************
        Return CSng(txtBox.Text)
    End Function

    Function Area(ByVal sngSideA As Single, ByVal sngSideB As Single) As Double
        '**********************************************************************************************************
        ' The purpose of this function is to calculate the area of a rectangle
        '**********************************************************************************************************
        Return sngSideA * sngSideB
    End Function

    Function Hypotenuse(ByVal sngSideA As Single, ByVal sngSideB As Single) As Double
        '**********************************************************************************************************
        ' The purpose of this function is to return the length of the hypotenuse of a rectangle.
        '**********************************************************************************************************
        Return Math.Sqrt(sngSideA ^ 2 + sngSideB ^ 2)
    End Function

    Private Sub btnCompute_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnCompute.Click
        '**********************************************************************************************************
        ' The purpose of this procedure is to compute the area and the length of the hypotenuse of a rectangle.
        ' The functions Area and Hypotenuse are used.
        '**********************************************************************************************************
        Dim sngHeight As Single, sngWidth As Single
        Dim dblArea As Double, dblHypotenuse As Double
        Dim strTemp As String

        ' get the numbers
        sngHeight = GetNumber(txtHeight)
        sngWidth = GetNumber(txtWidth)

        ' calculate the area and hypotenuse
        dblArea = Area(sngHeight, sngWidth)
        dblHypotenuse = Hypotenuse(sngHeight, sngWidth)

        ' display output
        strTemp = "The rectangle with height " & CStr(sngHeight) & " and width " & sngWidth
        strTemp &= " has area " & CStr(dblArea) & " and hypotenuse " & dblHypotenuse & "."
        txtOutput.Text = strTemp

    End Sub

    Private Sub btnExit_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnExit.Click
        End ' halt
    End Sub
End Class