(*----下面這個(gè)程序介紹了我們?cè)谑褂镁€(xiàn)程及未使用線(xiàn)程二種情況下，運(yùn)行該程序的反
應(yīng)。當(dāng)點(diǎn)UsedThread按鈕時(shí)，則建立一個(gè)線(xiàn)程，這時(shí)我們可以在程序進(jìn)行計(jì)算的同
時(shí)，改變窗體的尺寸及移動(dòng)它。當(dāng)按下NoUsedThread按鈕時(shí)，不建立線(xiàn)程，我們會(huì)發(fā)
現(xiàn)在程序沒(méi)有計(jì)算完之前根本不能做其它任何事情！

unit Unit1;

interface

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

type
  TForm1 = class(TForm)
    UsedThread: TBitBtn;
    NoUsedThread: TBitBtn;
    PRocedure UsedThreadClick(Sender: TObject);
    procedure NoUsedThreadClick(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

function MyThreadFunc(P:pointer):Longint;stdcall;
var
  i:longint;
  DC:HDC;
  S:string;
begin
  DC:=GetDC(Form1.Handle);
  for i:=0 to 500000 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(gè)句柄
  ThreadID:DWord;
begin
//創(chuàng)建線(xiàn)程，同時(shí)線(xiàn)程函數(shù)被調(diào)用
  hthread:=CreateThread(nil,0,@MyThreadfunc,nil,0,ThreadID);
  if hThread=0 then
  messagebox(Handle,'Didn’tCreateaThread',nil,MB_OK);
end;

procedure TForm1.NoUsedThreadClick(Sender: TObject);
begin
  MyThreadfunc(nil);
  //沒(méi)有創(chuàng)建線(xiàn)程時(shí)，直接調(diào)用線(xiàn)程函數(shù)
end;
end.