(OnKeyPress) Is arrow key pressed?

[Nitrogen]

Or....

Just use the raw windows messages:

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs;

type
  TForm1 = class(TForm)
  private
    { Private declarations }
  public
    procedure WMKeyDown(var Message : TWMKeyDown); message WM_KEYDOWN;
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

{ TForm1 }

procedure TForm1.WMKeyDown(var Message: TWMKeyDown);
begin
  if message.CharCode = VK_LEFT then
    form1.Left := form1.Left- 2;
  if message.CharCode = VK_RIGHT then
    form1.Left := form1.Left+ 2;
  if message.CharCode = VK_UP then
    form1.top := form1.top- 2;
  if message.CharCode = VK_DOWN then
    form1.top := form1.top+ 2;

end;

end.

Works quite well. With a delay and repeats.