Private Sub TabControl1_SelectedIndexChanged(sender as Object, e as EventArgs) _ 
     Handles TabControl1.SelectedIndexChanged

   MessageBox.Show("You are in the TabControl.SelectedIndexChanged event.")

End Sub

imports System
imports System.Drawing
imports System.Windows.Forms


public class TabControls : inherits Form
  public sub New()
    Size = new Size(325,375)

    dim tc as new TabControl()
    tc.Parent = me
    tc.Size = new Size(275,300)
    tc.Location = new Point(25,25)
    tc.Anchor = AnchorStyles.Top or AnchorStyles.Bottom or AnchorStyles.Left or AnchorStyles.Right
    tc.Alignment = TabAlignment.Top
    tc.Appearance = TabAppearance.Normal
    tc.HotTrack = true
    tc.Multiline = true
    tc.Padding = new Point(20,3)
    tc.SizeMode = TabSizeMode.FillToRight
    AddHandler tc.SelectedIndexChanged, AddressOf tc_Changed
    tc.Text = "Some text"

    dim img as Image = Image.FromFile("1.ico")
    dim imgList as new ImageList()
    imgList.Images.Add(img)
    tc.ImageList = imgList

    dim tpAddress as new TabPage()
    tpAddress.Parent = tc
    tpAddress.Text = "Address Book"

    dim tpDates as new TabPage()
    tpDates.Parent = tc
    tpDates.Text = "Date Book"

    dim tpToDo as new TabPage()
    tpToDo.Parent = tc
    tpToDo.Text = "ToDo List"

    dim tpMisc as new TabPage()
    tpMisc.Parent = tc
    tpMisc.Text = "A Really Long Tab"
    tpMisc.ImageIndex = 0

    dim lbl as new Label()
    lbl.Parent = tpAddress
    lbl.Text = "Put the Address book controls on this page."
    lbl.AutoSize = true
    lbl.Location = new Point(10,25)

    dim pnl as new Panel()
    pnl.Parent = tpDates
    pnl.BorderStyle = BorderStyle.Fixed3D
    pnl.Location = new Point(10,10)
    pnl.Anchor = AnchorStyles.Top or AnchorStyles.Bottom or _
          AnchorStyles.Left or AnchorStyles.Right
    pnl.Size = new Size(tpDates.Width - 20, tpDates.Height - 20)

    dim cal as new MonthCalendar()
    cal.Parent = pnl
    cal.Location = new Point(25,25)

    dim rtxt as new RichTextBox()
    rtxt.Parent = tpToDo
    rtxt.Dock = DockStyle.Fill
    rtxt.BorderStyle = BorderStyle.FixedSingle
  end sub

  public shared sub Main() 
    Application.Run(new TabControls())
  end sub

  private sub tc_Changed(ByVal sender as object,ByVal e as EventArgs)
    dim tc as TabControl = CType(sender,TabControl)
    Console.WriteLine("Button " + tc.SelectedIndex.ToString())
  end sub

end class