Public Class Textbox

     Inherits MicroFour.StrataFrame.UI.Web.TextBox

     .

     .

     .

End Class

Will it cause any errors when i try to add, update or delete record?

Protected Overrides Sub OnPaint(ByVal e As System.Windows.Forms.PaintEventArgs)
    '-- Make the base method call (DODEFAULT())
    MyBase.OnPaint(e)

    '-- Custom code here
End Sub

Now, if you attach to an event, then there is no base or DODEFAULT that you need to call; it will be done automatically.  In fact, there is no way to prevent the base methods from firing.  Only on method overrides do you need to call the base method.