Public Class Form1
    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 Button1 As System.Windows.Forms.Button
    Friend WithEvents Button2 As System.Windows.Forms.Button
    Friend WithEvents Button4 As System.Windows.Forms.Button
    Friend WithEvents Button3 As System.Windows.Forms.Button
    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
        Me.Button1 = New System.Windows.Forms.Button()
        Me.Button2 = New System.Windows.Forms.Button()
        Me.Button4 = New System.Windows.Forms.Button()
        Me.Button3 = New System.Windows.Forms.Button()
        Me.SuspendLayout()
        '
        'Button1
        '
        Me.Button1.Location = New System.Drawing.Point(32, 16)
        Me.Button1.Name = "Button1"
        Me.Button1.TabIndex = 0
        Me.Button1.Text = "Elevator #1"
        '
        'Button2
        '
        Me.Button2.Location = New System.Drawing.Point(32, 56)
        Me.Button2.Name = "Button2"
        Me.Button2.TabIndex = 1
        Me.Button2.Text = "Elevator #2"
        '
        'Button4
        '
        Me.Button4.Location = New System.Drawing.Point(32, 168)
        Me.Button4.Name = "Button4"
        Me.Button4.TabIndex = 2
        Me.Button4.Text = "Elevator #1--Constants"
        '
        'Button3
        '
        Me.Button3.Location = New System.Drawing.Point(32, 104)
        Me.Button3.Name = "Button3"
        Me.Button3.TabIndex = 3
        Me.Button3.Text = "Elevator #3"
        '
        'Form1
        '
        Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
        Me.ClientSize = New System.Drawing.Size(292, 273)
        Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.Button3, Me.Button4, Me.Button2, Me.Button1})
        Me.Name = "Form1"
        Me.Text = "Form1"
        Me.ResumeLayout(False)

    End Sub

#End Region

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim intCounter As Integer

        For intCounter = 2 To 20
            Console.WriteLine(intCounter)
        Next
    End Sub

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

        For intCounter = 2 To 20 Step 2
            Console.WriteLine(intCounter)
        Next
    End Sub

    Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click
        Const BOTTOM_FLOOR As Integer = 2
        Const TOP_FLOOR As Integer = 20
        Dim intcounter As Integer
        For intcounter = BOTTOM_FLOOR To TOP_FLOOR
            Console.WriteLine(intcounter)
        Next intcounter
    End Sub

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

        For intCounter = 3 To 20 Step 2
            Console.WriteLine(intCounter)
        Next
    End Sub
End Class
