Imports System.Drawing
Imports System.Windows.Forms

Public Class Form1
    Inherits Form
    Private tabControl1 As TabControl
    Private myTabRect As Rectangle

    Public Sub New()
        tabControl1 = New TabControl()
        Dim tabPage1 As New TabPage()

        ' Sets the tabs to be drawn by the parent window Form1.
        ' OwnerDrawFixed allows access to DrawItem. 
        tabControl1.DrawMode = TabDrawMode.OwnerDrawFixed

        tabControl1.Controls.Add(tabPage1)
        tabControl1.Location = New Point(25, 25)
        tabControl1.Size = New Size(250, 250)

        tabPage1.TabIndex = 0

        myTabRect = tabControl1.GetTabRect(0)

        ClientSize = New Size(300, 300)
        Controls.Add(tabControl1)

        AddHandler tabControl1.DrawItem, AddressOf OnDrawItem
    End Sub

    Private Sub OnDrawItem(ByVal sender As Object, ByVal e As DrawItemEventArgs)
        Dim g As Graphics = e.Graphics
        Dim p As New Pen(Color.Blue)
        g.DrawRectangle(p, myTabRect)
    End Sub

    Shared Sub Main()
        Application.Run(New Form1())
    End Sub
End Class

using System.Drawing;
using System.Windows.Forms;

public class Form1 : Form
{
    private TabControl tabControl1;
    private Rectangle myTabRect;

    public Form1()
    {
        tabControl1 = new TabControl();
        TabPage tabPage1 = new TabPage();

        // Sets the tabs to be drawn by the parent window Form1.
        // OwnerDrawFixed allows access to DrawItem. 
        tabControl1.DrawMode = TabDrawMode.OwnerDrawFixed;

        tabControl1.Controls.Add(tabPage1);
        tabControl1.Location = new Point(25, 25);
        tabControl1.Size = new Size(250, 250);

        tabPage1.TabIndex = 0;

        myTabRect = tabControl1.GetTabRect(0);

        ClientSize = new Size(300, 300);
        Controls.Add(tabControl1);

        tabControl1.DrawItem += new DrawItemEventHandler(OnDrawItem);
    }

    private void OnDrawItem(object sender, DrawItemEventArgs e)
    {
        Graphics g = e.Graphics;
        Pen p = new Pen(Color.Blue);
        g.DrawRectangle(p, myTabRect);
    }

    static void Main() 
    {
        Application.Run(new Form1());
    }
}

using namespace System::Drawing;
using namespace System::Windows::Forms;
public ref class Form1: public Form
{
private:
   TabControl^ tabControl1;
   Rectangle myTabRect;

public:
   Form1()
   {
      tabControl1 = gcnew TabControl;
      TabPage^ tabPage1 = gcnew TabPage;

      // Sets the tabs to be drawn by the parent window Form1.
      // OwnerDrawFixed allows access to DrawItem.
      tabControl1->DrawMode = TabDrawMode::OwnerDrawFixed;
      tabControl1->Controls->Add( tabPage1 );
      tabControl1->Location = Point(25,25);
      tabControl1->Size = System::Drawing::Size( 250, 250 );
      tabPage1->TabIndex = 0;
      myTabRect = tabControl1->GetTabRect( 0 );
      ClientSize = System::Drawing::Size( 300, 300 );
      Controls->Add( tabControl1 );
      tabControl1->DrawItem += gcnew DrawItemEventHandler( this, &Form1::OnDrawItem );
   }


private:
   void OnDrawItem( Object^ /*sender*/, DrawItemEventArgs^ e )
   {
      Graphics^ g = e->Graphics;
      Pen^ p = gcnew Pen( Color::Blue );
      g->DrawRectangle( p, myTabRect );
   }

};

int main()
{
   Application::Run( gcnew Form1 );
}