Delphi实现毫秒级别的倒计时实例代码

unit Unit1;

interface

uses

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

 ExtCtrls, StdCtrls, mmsystem;

type

 TForm1 = class(TForm)

  Edit1: TEdit;

  Edit2: TEdit;

  Edit3: TEdit;

  Button1: TButton;

  Button2: TButton;

  Timer1: TTimer;

  Label1: TLabel;

  Label2: TLabel;

  Label3: TLabel;

  procedure FormCreate(Sender: TObject);

  procedure Button1Click(Sender: TObject);

  procedure Timer1Timer(Sender: TObject);

  procedure Button2Click(Sender: TObject);

 private

  { Private declarations }

 public

  { Public declarations }

 end;

var

 Form1: TForm1;

 acttime1,acttime2:cardinal;

 smmcount,stimercount,spcount:single;

 htimeid:integer;

 iten:integer;

 protimecallback:tfntimecallback;

 procedure timeproc(utimerid, umessage: uint; dwuser, dw1, dw2: dword) stdcall;

 procedure proendcount;

implementation

{$R *.DFM}

//timesetevent的回调函数

procedure proendcount;

begin

 acttime2:=gettickcount-acttime1;

 form1.button2.enabled :=false;

 form1.button1.enabled :=true;

 form1.timer1.enabled :=false;

 smmcount:=60;

 stimercount:=60;

 spcount:=-1;

 timekillevent(htimeid);

end;

procedure timeproc(utimerid, umessage: uint; dwuser, dw1, dw2: dword) stdcall;

begin

 form1.edit2.text:=floattostr(smmcount);

 smmcount:=smmcount-0.01;

end;

procedure TForm1.FormCreate(Sender: TObject);

begin

 button1.caption :='开始倒计时';

 button2.caption :='结束倒计时';

 button2.enabled :=false;

 button1.enabled :=true;

 timer1.enabled :=false;

 smmcount:=60;

 stimercount:=60;

 spcount:=60;

end;

procedure TForm1.Button1Click(Sender: TObject);

var

 lgtick1,lgtick2,lgper:tlargeinteger;

 ftemp:single;

begin

 button2.enabled :=true;

 button1.enabled :=false;

 timer1.enabled :=true;

 timer1.interval :=10;

 protimecallback:=timeproc;

 htimeid:=timesetevent(10,0,protimecallback,1,1);

 acttime1:=gettickcount;

 //获得系统的高性能频率计数器在一毫秒内的震动次数

 queryperformancefrequency(lgper);

 ftemp:=lgper/1000;

 iten:=trunc(ftemp*10);

 queryperformancecounter(lgtick1);

 lgtick2:=lgtick1;

 spcount:=60;

 while spcount>0 do

 begin

  queryperformancecounter(lgtick2);

  //如果时钟震动次数超过10毫秒的次数则刷新edit3的显示

  if lgtick2 - lgtick1 > iten then

  begin

   lgtick1 := lgtick2;

   spcount := spcount - 0.01;

   edit3.text := floattostr(spcount);

   application.processmessages;

  end;

 end;

end;

procedure TForm1.Timer1Timer(Sender: TObject);

begin

 edit1.text := floattostr(stimercount);

 stimercount:=stimercount-0.01;

end;

procedure TForm1.Button2Click(Sender: TObject);

begin

 proendcount;

 //显示从开始记数到记数实际经过的时间

 showmessage('实际经过时间'+inttostr(acttime2)+'毫秒');

end;

end.