unit1.pas

delphi典型实验代码

unit Unit1;

interface

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

type
  TForm1 = class(TForm)
    Button1: TButton;
    Edit1: TEdit;
    Label1: TLabel;
    Timer1: TTimer;
    Label2: TLabel;
    Label3: TLabel;
    Label4: TLabel;
    ScrollBar1: TScrollBar;
    Label5: TLabel;
    procedure Timer1Timer(Sender: TObject);
    procedure Button1Click(Sender: TObject);
    procedure FormCreate(Sender: TObject);
    procedure ScrollBar1Change(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;
  tar_time:ttime;
  djs,start:boolean;
  dx,dy:integer;
implementation

{$R *.dfm}

procedure TForm1.Timer1Timer(Sender: TObject);
begin
  //***********************************//
  label2.caption:=datetimetostr(now);
  if djs then

     label3.caption:=timetostr(tar_time-time);


  //*********************************//
    if start then
    begin
      if label4.left+label4.width>form1.clientwidth then dx:=-dx;
      if label4.top+label4.height>form1.clientheight then dy:=-dy;
      label4.left:=label4.left+dx;
      label4.top:=label4.top +dy;
   if label4.top<0 then dy:=-dy;   //屏幕上端
   if label4.left<0 then dx:=-dx;  //左端

   if(timetostr(tar_time-time)='0:00:00') then
              begin
               button1.Caption:='开始倒计时';
              djs:=false;
              start:=false;
              end
     end
   end;

procedure TForm1.Button1Click(Sender: TObject);
begin
   djs:=not djs;
   if djs then
      begin
      start:=true;
        tar_time:=time+encodetime(0,0,strtoint(edit1.Text),0);
        button1.Caption:='停止倒计时';
      end
   else
      begin
        start:=false;
        button1.Caption:='开始倒计时';
      end
end;

procedure TForm1.FormCreate(Sender: TObject);
  var d:real;
  speed:integer;
begin
//***************/ /
djs:=false;
 //*********************************//
 speed:=20;
 d:=30*pi/180;
 dx:=round(speed*cos(d));
 dy:=round(speed*sin(d));
 button1.Caption:='开始倒计时';
 edit1.text:='0';
 label3.caption:='0:00:00';
end;

procedure TForm1.ScrollBar1Change(Sender: TObject);
begin
timer1.interval:=scrollbar1.position ;
end;

end.