unit Unit1;

 

interface

 

uses

  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms,

  Dialogs, StdCtrls, WinSpool;

 

type

  TForm1 = class(TForm)

    btnStart: TButton;

    cbPrinters: TComboBox;

    procedure btnStartClick(Sender: TObject);

    procedure FormCreate(Sender: TObject);

  end;

 

var

  Form1: TForm1;

 

implementation

 

{$R *.dfm}

 

procedure TForm1.FormCreate(Sender: TObject);

var

  PrintersInfo: array of TPrinterInfo5;

  I, Needed, Returned: DWORD;

begin

  EnumPrinters(PRINTER_ENUM_LOCAL, nil, 5, nil,

    0, Needed, Returned);

  SetLength(PrintersInfo, Needed div SizeOf(TPrinterInfo5));

  if EnumPrinters(PRINTER_ENUM_LOCAL, nil, 5, PrintersInfo,

    Needed, Needed, Returned) then

    if Returned > 0 then

    begin

      for I := 0 to Returned - 1 do

        cbPrinters.Items.Add(PrintersInfo[I].pPrinterName);

      btnStart.Enabled := True;

      cbPrinters.ItemIndex := 1;

    end;

end;

 

procedure TForm1.btnStartClick(Sender: TObject);

var

  hPrinter, hChanges: THandle;

  NotifyOption: TPrinterNotifyOptions;

  NotifyTipes: TPrinterNotifyOptionsType;

  Field: TPrinterNotifyInfoData;

begin

  if OpenPrinter(PChar(cbPrinters.Items.Strings[cbPrinters.ItemIndex]),

    hPrinter, nil) then

  try

 

    NotifyTipes.wType := JOB_NOTIFY_TYPE;

    NotifyTipes.Reserved0 := 0;

    NotifyTipes.Reserved1 := 0;

    NotifyTipes.Reserved2 := 0;

    NotifyTipes.Count := 1;

    NotifyTipes.pFields := @Field;

 

    NotifyOption.Version := 2;

    NotifyOption.Flags := PRINTER_CHANGE_ALL;

    NotifyOption.Count := 1;

    NotifyOption.pTypes := @NotifyTipes;

    

    hChanges := FindFirstPrinterChangeNotification(hPrinter, PRINTER_CHANGE_ALL,

      0, @NotifyOption);

    if hChanges = INVALID_HANDLE_VALUE then

      RaiseLastOSError

    else

    try

      case WaitForSingleObject(hChanges, INFINITE) of

        WAIT_OBJECT_0: ShowMessage('Есть изменения');

        WAIT_FAILED: RaiseLastOSError;

      end;

    finally

      FindClosePrinterChangeNotification(hChanges);

    end;

  finally

    ClosePrinter(hPrinter);

  end;

end;

 

end.