unit PS_useThread;

interface

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

type

TForm1 = class(TForm)
  UsedThread: TButton;
  NoUsedThread: TButton;
  procedure UsedThreadClick(Sender: TObject);
  procedure NoUsedThreadClick(Sender: TObject);
  end;

var

Form1: TForm1;

implementation

{$R *.DFM}

//這是線程函數，它可以放在下面程序的任何地方

function MyThreadFunc(P:pointer):Longint;stdcall;
var
i:integer;
DC:HDC;
S:string;
begin
  DC:=GetDC(Form1.Handle);
  for i:=0 to 100000 do begin
    S:=Inttostr(i);
    Textout(DC,10,10,Pchar(S),length(S));
    end;
  ReleaseDC(Form1.Handle,DC);
end;

procedure TForm1.UsedThreadClick(Sender: TObject);
var
  hThread:Thandle;//定義一個句柄
  ThreadID:DWord;
begin
//創建線程，同時線程函數被調用
  hthread:=CreateThread(nil,0,@MyThreadfunc,nil,0,ThreadID);
  if hThread=0 then
    messagebox(Handle,'Didn’t Create a Thread',nil,MB_OK);
end;

procedure TForm1.NoUsedThreadClick(Sender: TObject);
begin
  MyThreadfunc(nil);
//沒有創建線程時，直接調用線程函數
end;

end.