c++ builder 学习（2） 定时器的使用

1 控件System 中的TTimer

打开定时器： Timer1->Enabled = true;

关闭定时器：       Timer1 ->Enabled = false;

TTimer的InterVal属性设置定时器的时间

eg：实现字幕滚动

void __fastcall TForm2::FormPaint(TObject *Sender)
{
  Label1->Canvas->TextOut(i, j, "Hello from the canvas");
  /*TRect rect;
  rect.Left = 100;
  rect.right = 20;
  rect.Bottom = 500;
  rect.top  = 30;
  DrawText(Form2->Canvas->Handle,"hello world",12,&rect,1); */

}

void __fastcall TForm2::Label1MouseEnter(TObject *Sender)
{

 //Form2-> Canvas->TextOutA(0,0,"hello world");
 Timer1 ->Enabled = false;

}
//---------------------------------------------------------------------------
void __fastcall TForm2::Label1MouseLeave(TObject *Sender)
{
//Form2-> Canvas->TextOutA(0,0,"");
   //MessageBox(Application->Handle,"bb","aa",MB_OK);
//Invalidate();
Timer1->Enabled = true;

}
//---------------------------------------------------------------------------
void __fastcall TForm2::Timer1Timer(TObject *Sender)
{
   i=i+10;
   //if(i>50)
   //i = 0;

   Invalidate();
   //SetBkMode(Canvas->Handle,TRANSPARENT);

}