[NumLock]

Код:

unit Unit1;

interface

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

type
  TForm1 = class(TForm)
    ColorBox1: TColorBox;
    ColorDialog1: TColorDialog;
    ColorBox2: TColorBox;
    procedure FormCreate(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
    SaveColorBoxWindowProc: TWndMethod;
    procedure ColorBoxWindowProc(var Message: TMessage);
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.FormCreate(Sender: TObject);
begin
  SaveColorBoxWindowProc:=ColorBox1.WindowProc;
  ColorBox1.WindowProc:=ColorBoxWindowProc;
end;

procedure TForm1.ColorBoxWindowProc(var Message: TMessage);
begin
  if Message.Msg=WM_LBUTTONUP then
  begin
  end else if Message.Msg=WM_LBUTTONDBLCLK then ColorDialog1.Execute
  else SaveColorBoxWindowProc(Message);
end;

end.