uses Series,TeeEdiGene;

private
    Series1: TPieSeries;

procedure TnPOP_check_model.insertcurrve_model_tot;
var
    curve_today_tot:array [0..30] of string;
begin
    Series1:=TPieSeries.Create(dbchart1);
    Series1.ParentChart:= dbChart1;
    Series1.Clear;
    Series1.Marks.Visible:=true;
    Series1.Marks.Style:=smsValue;
    Series1.SeriesColor:=cxcolorcombobox1.ColorValue;
    Series1.Title:='SUM_'+'-'+'Q';

    qry_temp1.Close;
    qry_temp1.SQL.Text:='select type,bad_count from press_check2';
    qry_temp1.Open;
      if qry_temp1.RecordCount>0 then
       begin
&n

方法：

uses DateUtils;

 SecondsBetween(Now(),StrToDateTime(Edit1.Text));