Работа в отдельном потоке, которая не мешает основной программе.

Автор: Xavier Pacheco

unit ThrdU;
interface
uses
  Classes;
type
  TTestThread = class(TThread)
  private
    Answer: integer;
  protected
    procedure GiveAnswer;
    procedure Execute; override;
  end;
implementation
uses SysUtils, Main;
{ TTestThread }
procedure TTestThread.GiveAnswer;
begin
  MainForm.Edit1.Text := InttoStr(Answer);
end;
procedure TTestThread.Execute;
var
  I: Integer;
begin
  FreeOnTerminate := True;
  for I := 1 to 2000000 do
  begin
    if Terminated then
      Break;
    Inc(Answer, Round(Abs(Sin(Sqrt(I)))));
    Synchronize(GiveAnswer);
  end;
end;
end.

unit Main;
interface
uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  StdCtrls, ThrdU;
type
  TMainForm = class(TForm)
    Edit1: TEdit;
    Button1: TButton;
    Memo1: TMemo;
    Label1: TLabel;
    Label2: TLabel;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;
var
  MainForm: TMainForm;
implementation
{$R *.DFM}
procedure TMainForm.Button1Click(Sender: TObject);
begin
  TTestThread.Create(False);
end;
end.