大家帮我看看我这段代码有什么问题，关于删除门禁机白名单的。

begin

       clk.Port:=cbComPort.ItemIndex+1;

       clk.baudrate:=StrToInt(cbComRate.Text);

       clk.clock_id:=StrToInt('$'+edClock_id.Text);

  

       ClosePort(@clk, clk.CommStyle);

       if OpenPort(@clk, clk.CommStyle) then

       begin

         Panel5.Visible := True;

         //刪除離職

         WhiteList.Close;

         WhiteList.SQL.Clear;

         WhiteList.SQL.Add('SELECT * FROM WhiteList WHERE CardNo NOT IN(SELECT PNL FROM P_PERSON_P20140922 WHERE [Status]<>''R'')');

         WhiteList.Open;



         if WhiteList.RecordCount >0 then

         begin

           WhiteList.First;

           //while not WhiteList.Eof do

           for L:=0 to WhiteList.RecordCount-1 do

           begin

             Showmessage(WhiteList.FieldByName('CardNo').AsString);

             if DeleteAllowedCard(clk.hPort,pChar(WhiteList.FieldByName('CardNo').AsString)) then //这里经常出错，有时可以有时又不行

             begin

               //刪除數據庫

               WhiteList.Delete;

               Panel5.Caption := Format('正在刪除卡機第:%d笔记录, 剩余记录数:%d(总共记录数:%d)', [WhiteList.RecNO, WhiteList.RecordCount-WhiteList.RecNO, WhiteList.RecordCount]);

               Panel5.Refresh;

               inc(K);

             end else

             begin

               Showmessage('刪除失敗，無法連接！');

               //break;

             end;

             WhiteList.Next;

           end;

         end;



         Showmessage(Format('本次共刪除:%d笔！！',[k]));

         PageControl1.Enabled := True;

         Panel5.Visible :=False;

         //

         if ReadClockTime(clk.hPort, CurTime) then

         Label5.Caption:=formatDateTime(LongDateFormat+' '+LongTimeFormat, CurTime);

       end else

       begin

         //連接失敗

         PageControl1.Enabled := True;

         Panel5.Visible :=False;

         //ClosePort(@clk, clk.CommStyle);

         //exit;

         break;

       end;

       ClosePort(@clk, clk.CommStyle);

end;