其中主要程序如下：

type

 TMainFrm = class(TForm)

   Pages: TPageControl;

   PrinterSht: TTabSheet;

   PrinterLst: TListBox;

...

 private

   procedure SpollerStatus(var Msg:TWMSpoolerStatus); message WM_SPOOLERSTATUS;

...

uses

 WinSpool, ExtCtrls;

procedure TMainFrm.SpollerStatus(var Msg:TWMSpoolerStatus);

var

 tbt:Byte;

 Needed,Returned:DWORD;

 ResultBuffer:Pointer;

 i,x,Count:Integer;

 Pi:PJobInfo1;

 hPrinter:THandle;

 List:TListBox;

 Lbl:TLabel;

begin

 for i:=1 to Pages.PageCount-1 do begin

   hPrinter:=Pages.Pages[i].Tag;

   List:=Pages.Pages[i].Controls[0] as TListBox;

   Lbl:=((Pages.Pages[i].Controls[1] as TPanel)

       .Controls[0] as TLabel);

   List.Clear;

   EnumJobs(hPrinter,0,Msg.JobsLeft,1,@tbt,0,Needed,Returned);

   if Needed=0 then begin

     Lbl.Caption:='0 个作业';

     Continue;

   end;

   Count:=Needed;

   if Count<=0 then begin

     Lbl.Caption:='0 个作业';

     Continue;

   end;

   GetMem(ResultBuffer,Count);

   try

     EnumJobs(hPrinter,0,Msg.JobsLeft,1,ResultBuffer,Needed,Needed,Returned);

     if Returned>Msg.JobsLeft then begin

       Lbl.Caption:='0 个作业';

       Continue;

     end;

     Lbl.Caption:=IntToStr(Returned)+' 个作业';

     Pi:=ResultBuffer;

     for x:=0 to Returned-1 do begin

       List.Items.Add(Pi^.pDocument);

       Pi:=PJobInfo1(LongInt(Pi)+Sizeof(Pi^));

     end;

   finally

     FreeMem(ResultBuffer,Count);

   end;

 end;

 Msg.Result:=0;

end;

procedure TMainFrm.FormCreate(Sender: TObject);

var

 tbt:Byte;

 Needed,Returned:DWORD;

 ResultBuffer:Pointer;

 x,Count:Integer;

 Pi:PPrinterInfo1;

 Sheet:TTabSheet;

 hPrinter:THandle;

 Panel:TPanel;

begin

 PrinterLst.Clear;

 EnumPrinters(PRINTER_ENUM_LOCAL,'',1,@tbt,0,Needed,Returned);

 if Needed=0 then Exit;

 Count:=Needed;

 GetMem(ResultBuffer,Count);

 EnumPrinters(PRINTER_ENUM_LOCAL,'',1,ResultBuffer,Needed,Needed,Returned);

 Pi:=ResultBuffer;

 for x:=0 to Returned-1 do begin

   PrinterLst.Items.Add(Pi^.pName);

   Pi:=PPrinterInfo1(LongInt(Pi)+Sizeof(Pi^));

   Sheet:=TTabSheet.Create(Self);

   with Sheet do begin

     PageControl:=Pages;

     Caption:=PrinterLst.Items[PrinterLst.Items.Count-1];

     OpenPrinter(PChar(Caption),hPrinter,nil);

     Tag:=hPrinter;

     ClosePrinter(hPrinter);

     with TListBox.Create(Self) do begin

       Parent:=Sheet;

       Align:=alClient;  

     end;

     Panel:=TPanel.Create(Self);

     with Panel do begin

       Parent:=Sheet;

       Align:=alTop;

       Height:=20;

       BevelOuter:=bvNone;

     end;

     with TLabel.Create(Self) do begin

       Parent:=Panel;

       Left:=10;

       Top:=3;

       Caption:='0 个作业';

     end;

   end;

 end;

 FreeMem(ResultBuffer,Count);

end;

procedure TMainFrm.FormDestroy(Sender: TObject);

var

 i,j:Integer;

begin

 for i:=1 to Pages.PageCount-1 do

   with Pages.Pages[i] do begin

     ((Controls[1] as TPanel).Controls[0] as TLabel).Free;

     for j:=0 to ControlCount-1 do

       Controls[0].Free;

     Free;

   end;

end;