Michal,

Declare the structs something like this

struct PRINTER_NOTIFY_INFO
{
 public uint Version;
 public uint Flags;
 public uint Count;
 // Array of PRINTER_NOTIFY_INFO_DATA follows
}

struct PRINTER_NOTIFY_INFO_DATA
{
 public ushort Type;
 public ushort Field;
 public uint Reserved;
 public uint Id;
 public uint cbBuf;  // or adwData[0]
 public IntPtr pBuf; // or uint adwData[1]
}

Declare FindNextPrinterChangeNotification like this

static extern bool FindNextPrinterChangeNotification(..., out IntPtr
ppPrinterNotifyInfo);

and finally call it like this

IntPtr pNotifyInfo;
if ( FindNextPrinterChangeNotification( ..., out pNotifyInfo ) ) {
 PRINTER_NOTIFY_INFO info =
(PRINTER_NOTIFY_INFO)Marshal.PtrToStructure(
   pNotifyInfo, typeof(PRINTER_NOTIFY_INFO) );
 int pData = (int)pNotifyInfo +
   Marshal.SizeOf( typeof(PRINTER_NOTIFY_INFO) );
 PRINTER_NOTIFY_INFO_DATA[] data =
   new PRINTER_NOTIFY_INFO_DATA[info.Count];
 for ( uint i = 0; i < info.Count; i++ ) {
   data[i] = (PRINTER_NOTIFY_INFO_DATA)Marshal.PtrToStructure(
     (IntPtr)pData, typeof(PRINTER_NOTIFY_INFO_DATA) );
   pData += Marshal.SizeOf( typeof(PRINTER_NOTIFY_INFO_DATA) );
 }
 FreePrinterNotifyInfo( pNotifyInfo );
}

Mattias

i have the same problem, and i tried to solve it that way, but the count of the info is always zero
int pdwChange = 0;
       IntPtr ptr = IntPtr.Zero;
       PRINTER_NOTIFY_OPTIONS  notifyOptions = new PRINTER_NOTIFY_OPTIONS();
       notifyOptions.Count = 1;
       notifyOptions.dwFlags = PRINTER_NOTIFY_OPTIONS_REFRESH;
       notifyOptions.dwVersion = 2;
       bool nxt = FindNextPrinterChangeNotification(whand, out pdwChange, notifyOptions, out ptr);
       PRINTER_NOTIFY_INFO info = (PRINTER_NOTIFY_INFO)Marshal.PtrToStructure(ptr, typeof(PRINTER_NOTIFY_INFO));
     

From http://developmentnow.com/g/21_2004_2_0_0_105339/Problems-with-FindNextPrinterCh
angeNotification-in-C.ht