Private m_handle as Boolean

e.handled = me.m_handled

If m_handled = true Then
    e.Handled = true
    return
end if

Public Class MyComboBox
    Inherits ComboBox
    Private m_handled As Boolean = False
    Protected Overrides Sub OnKeyUp(ByVal e As System.Windows.Forms.KeyEventArgs)
        If m_handled = True Then
            e.Handled = True
            Return
        End If
        Console.WriteLine(e.KeyCode)
        Select Case e.KeyCode
            Case Keys.Control
            Case Keys.ControlKey

            Case Keys.ShiftKey
            Case Keys.Shift

            Case Keys.Delete
            Case Keys.End
            Case Keys.PageDown
            Case Keys.PageUp
            Case Keys.Pause
            Case Keys.Home
            Case Keys.Help

            Case Keys.Enter
            Case Keys.Back
            Case Keys.Escape
            Case Keys.Tab
            Case Keys.None >  222 

            Case Else
                Dim m As String = Me.Text
                If Not (m = Nothing) Then
                    For Each c As String In Me.Items
                        If c.ToUpper.StartsWith(m.ToUpper) Then
                            Me.SelectedItem = CObj(c)
                            Me.Select(m.Length, Me.Text.Length - m.Length)
                            Exit For  ' by Sa Поменял эту строчку 
                        End If
                    Next
                End If
        End Select
        MyBase.OnKeyUp(e)
    End Sub

    Protected Overrides Sub OnKeyPress(ByVal e As System.Windows.Forms.KeyPressEventArgs)
        e.Handled = Me.m_handled
        MyBase.OnKeyPress(e)
    End Sub

    Protected Overrides Sub OnKeyDown(ByVal e As System.Windows.Forms.KeyEventArgs)
        If e.Control = True Then
            Me.m_handled = True
            Return
        End If
        Me.m_handled = False
        MyBase.OnKeyDown(e)
    End Sub

    Protected Overrides Function ProcessCmdKey(ByRef msg As Message, ByVal keyData As Keys) As Boolean
        If keyData = (Keys.Control Or Keys.Delete) Then
            Return True
        End If
        Return MyBase.ProcessCmdKey(msg, keyData)
    End Function
End Class

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