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Unit1.cpp：源码内容

							//---------------------------------------------------------------------------
#include <vcl.h>
#pragma hdrstop
#include "Unit1.h"
#include "mmsystem.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
{
TimerID = 0;
}
//---------------------------------------------------------------------------
double _sqrt(double a)
{
  double x1 = 0.0;
  double x2 = a/2;
  while(x1!= x2)
  {
     x1 = x2;
     x2 = (x1 + a/x1)/2;
  }
  return x1;
}
//------
void __fastcall TForm1::Button1Click(TObject *Sender)
{
TimerID = timeSetEvent(1000, 0, (LPTIMECALLBACK)TimeProc, 0,TIME_PERIODIC); // 设定多媒体定时器,1000ms
    if(TimerID == 0)    {
                             ShowMessage("创建失败");
                         }
}
//---------------------------------------------------------------------------
void CALLBACK TForm1::TimeProc(UINT uID,UINT uMsg, DWORD dwUser,DWORD dw1,DWORD dw2)
{
    static int a=0;
    a++;
    Form1->Label1->Caption=IntToStr(a);
    //Form1->Label1->Caption = Now();
}
void __fastcall TForm1::FormClose(TObject *Sender, TCloseAction &Action)
{
if(TimerID != 0)    {
        timeKillEvent(TimerID); // 释放定时器
                    }
}
//---------------------------------------------------------------------------

						