Public Class Textboxtest
    Inherits Windows.Forms.TextBox
    Friend WithEvents ListBox1 As System.Windows.Forms.ListBox
    Private components As System.ComponentModel.IContainer
 
 
    Protected Overrides Sub OnTextChanged(ByVal e As System.EventArgs)
        Me.ListBox1.Items.Clear()
        For i As Integer = 0 To Me.AutoCompleteCustomSource.Count - 1
            If Me.AutoCompleteCustomSource.Item(i).Contains(Me.Text) Then
                Me.ListBox1.Items.Add(Me.AutoCompleteCustomSource.Item(i))
            End If
        Next
        If Me.ListBox1.Items.Count <= 6 Then
            Dim isas As New System.Drawing.Size(Me.Width, _
              Me.ListBox1.Items.Count * Me.ListBox1.ItemHeight)
            Me.ListBox1.Size = New Drawing.Size(Me.Width, _
            Me.ListBox1.Items.Count * Me.ListBox1.ItemHeight)
        Else
            Me.ListBox1.Size = New Drawing.Size(Me.Width, 6 * _
              Me.ListBox1.ItemHeight)
        End If
        Me.ListBox1.Location = New Drawing.Point(Me.Location.X, Me.Location.Y + _
          Me.Size.Height)
        MyBase.OnTextChanged(e)
    End Sub
 
    Protected Overrides Sub OnKeyDown(ByVal e As _
      System.Windows.Forms.KeyEventArgs)
        If e.KeyCode = Keys.Return Then
            Me.AutoCompleteCustomSource.Add(Me.Text)
        End If
        MyBase.OnKeyDown(e)
    End Sub
 
 
 
    Public Sub New()
        InitializeComponent()
    End Sub
 
    Private Sub InitializeComponent()
        Me.ListBox1 = New System.Windows.Forms.ListBox()
        Me.SuspendLayout()
        '
        'ListBox1
        '
        Me.ListBox1.FormattingEnabled = True
        Me.ListBox1.Location = New System.Drawing.Point(0, 0)
        Me.ListBox1.Name = "ListBox1"
        Me.ListBox1.Size = New System.Drawing.Size(120, 96)
        Me.ListBox1.TabIndex = 0
        Me.ResumeLayout(False)
 
    End Sub
End Class