unit U_ZdyInput; interface uses Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms, Dialogs; type TfrmZdyInput = class(TForm) procedure FormDestroy(Sender: TObject); private { Private declarations } public { Public declarations } end; var frmZdyInput: TfrmZdyInput; implementation {$R *.dfm} procedure TfrmZdyInput.FormDestroy(Sender: TObject); begin frmZdyInput:=nil; end; end.