时间的运算

procedure TForm1.Button1Click(Sender: TObject);
var
  i: Real;
begin
  i := StrToDate(\'2008-1-1\') - StrToDate(\'2007-1-1\');
  ShowMessage(FloatToStr(i));  //返回的结果是365天

  i := StrToDate(\'2009-1-1\') - StrToDate(\'2008-1-1\');
  ShowMessage(FloatToStr(i));  //返回的结果是366天
end;