This is code for Arabic ComboBox component you can change the "TComboBox" class to dervie new components as follow:
unit arab; interface uses Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs, ExtCtrls,stdctrls; type TACombo = class (TComboBox) private { Private declarations } procedure CreateParams(var Params: TCreateParams); override; end; implementation procedure TACombo.CreateParams(var Params: TCreateParams); begin inherited CreateParams(Params); { call the inherited first } with Params do ExStyle := ExStyle or WS_EX_RTLREADING or WS_EX_RIGHT; end; end.