Управление процессами, потоками (нитями) в критической секции

unit Threads2;
 
interface
 
uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;
 
type
  TForm2 = class(TForm)
    Label1: TLabel;
    Button2: TButton;
    Button1: TButton;
    GroupBox3: TGroupBox;
    ScrollBar1: TScrollBar;
    Button3: TButton;
    Button4: TButton;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
    procedure Button3Click(Sender: TObject);
    procedure Button4Click(Sender: TObject);
    procedure FormCreate(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;
 
type  //Ñîçäåì êëàñ ïîòîêà 1
  TMyThread1 = class(TThread)
  private
   {Private declarations }
  protected
    procedure Execute; override;
    procedure DoSomething;
  end;
        //Ñîçäåì êëàñ ïîòîêà 2
type
  TMyThread2 = class(TThread)
  private
   {Private declarations }
  protected
    procedure Execute; override;
    procedure DoSomething;
  end;
var
  Form2: TForm2;
  Thread1: TMyThread1;
  Thread2: TMyThread2;
   flag: Boolean;
   Sect: TRTLCriticalSection;
   GlobalData: Integer; //Ïåðåìåííàÿ äëÿ ñåìàôîðà
 
implementation
 
{$R *.dfm}
 
   {Ïîòîê 1}
procedure TmyThread1.Execute;
begin
  While not terminated do
   begin
    Synchronize(DoSomething); //Ñèíõðîíèçàöèÿ ïîòîêà ñ ïðîãðàììîé
   end;
end;
 
procedure TMyThread1.DoSomething;
begin
  Form2.ScrollBar1.Position:= 10;
end;
        {Ïîòîê 2}
procedure TmyThread2.Execute;
begin
  While not terminated do
   begin
    Synchronize(DoSomething); //Ñèíõðîíèçàöèÿ ïîòîêà ñ ïðîãðàììîé
   end;
end;
 
procedure TMyThread2.DoSomething;
begin
  Form2.ScrollBar1.Position:= 90;
end;
 
procedure TForm2.Button1Click(Sender: TObject);
begin
  if flag = false then
   begin
     Thread1.Create(False);
     THread1.Priority:= tpLowest;
      EnterCriticalSection(Sect);
      GlobalData:=GlobalData+10;
      Button1.Enabled:= False;
      Button2.Enabled:=true;
   end
   else ShowMessage('Êðèòè÷åñêàÿ òî÷êà óæå èñïîëüçóåòñÿ <> Çàíÿòà ïîòîêîì');
end;
 
procedure TForm2.Button2Click(Sender: TObject);
begin
  Thread1.Terminate; Thread1.Free;
  LeaveCriticalSection(Sect);
  GlobalData:=0;
   //îòêëþ÷àåì êíîïêó
  Button2.Enabled:= False;
   // âêëþ÷àåì êíîïêó
  Button1.Enabled:= True;
end;
 
procedure TForm2.Button3Click(Sender: TObject);
begin
    if flag = false then
   begin
     Thread2.Create(False);
     THread2.Priority:= tpTimeCritical;
     EnterCriticalSection(Sect);
     GlobalData:=GlobalData+100;
     Button3.Enabled:= False;
     Button4.Enabled:=true;
   end
   else ShowMessage('Êðèòè÷åñêàÿ òî÷êà óæå èñïîëüçóåòñÿ <> Çàíÿòà ïîòîêîì');
end;
 
procedure TForm2.Button4Click(Sender: TObject);
begin
  Thread1.Terminate; Thread1.Free;
  LeaveCriticalSection(Sect);
  GlobalData:=0;
   //îòêëþ÷àåì êíîïêó
  Button4.Enabled:= False;
   // âêëþ÷àåì êíîïêó
  Button3.Enabled:= True;
end;
 
procedure TForm2.FormCreate(Sender: TObject);
begin
  InitializeCriticalSection(Sect);
  flag:= False;
end;
 
end.