Public Class Paziente

   Private _Sesso As String
   Public Property Sesso() As String
       Get
           Return _Sesso
       End Get
       Set(ByVal value As String)
           If value IsNot Nothing Then
               value = Char.ToUpper(value)
               If value = "M" Or value = "F" Then
                   _Sesso = value
               Else
      throw new exception("Error sex must be M or F")
               End If
           Else
               _Sesso = Nothing
           End If
       End Set
   End Property
End Class

when i set Sesso in the form if i set some different from M or F
occur an error
and the focus remain in the textbox

how to capture the error message ex.message to display in the user interface
?

Thanks
FLAVIO

end class