代碼文件:
unit Unit1;
interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls;
type
TForm1 = class(TForm)
Button1: TButton;
procedure Button1Click(Sender: TObject);
procedure FormDestroy(Sender: TObject);
end;
var
Form1: TForm1;
implementation
{$R *.dfm}
var
f: Integer;
hWaitableTimer: THandle; {等待定時器對象的句柄}
function MyThreadFun(p: Pointer): DWord; stdcall;
var
i,y: Integer;
begin
Inc(f);
y := 20 * f;
if WaitForSingleObject(hWaitableTimer, INFINITE) = WAIT_OBJECT_0 then
begin
for i := 0 to 1000 do
begin
Form1.Canvas.Lock;
Form1.Canvas.TextOut(20, y, IntToStr(i));
Form1.Canvas.Unlock;
Sleep(1);
end;
end;
Result := 0;
end;
procedure TForm1.Button1Click(Sender: TObject);
var
ThreadID: DWord;
DueTime: Int64;
begin
hWaitableTimer := CreateWaitableTimer(nil, True, nil);
DueTime := 0;
SetWaitableTimer(hWaitableTimer, DueTime, 0, nil, nil, False);
Repaint; f := 0;
CreateThread(nil, 0, @MyThreadFun, nil, 0, ThreadID);
CreateThread(nil, 0, @MyThreadFun, nil, 0, ThreadID);
CreateThread(nil, 0, @MyThreadFun, nil, 0, ThreadID);
end;
procedure TForm1.FormDestroy(Sender: TObject);
begin
CloseHandle(hWaitableTimer);
end;
end.
窗體文件:
object Form1: TForm1
Left = 0
Top = 0
Caption = 'Form1'
ClIEntHeight = 116
ClIEntWidth = 179
Color = clBtnFace
Font.Charset = DEFAULT_CHARSET
Font.Color = clWindowText
Font.Height = -11
Font.Name = 'Tahoma'
Font.Style = []
OldCreateOrder = False
OnDestroy = FormDestroy
PixelsPerInch = 96
TextHeight = 13
object Button1: TButton
Left = 96
Top = 83
Width = 75
Height = 25
Caption = 'Button1'
TabOrder = 0
OnClick = Button1Click
end
end
下面是一個每隔半秒鐘(500ms)執行一次的例子(窗體文件同上):
本例效果圖:
