🚀 go-pugleaf

On Wed, 25 Jan 2006 11:23:43 -0800, "Remy Lebeau \(TeamB\)" 
>So?  You can filter those out before deciding to scan your devices.

Filtering DBT_DEVTYP_VOLUME info with the DBTF_MEDIA works great in
order to determine whether or not the event was generated by a media
change or by an actual device change. 

Actual device :
DBT_DEVICEARRIVE/REMOVE::dbch_devicetype=2::DBTF_MEDIA=0 
DBT_DEVICEARRIVE/REMOVE::dbch_devicetype=2::DBTF_MEDIA=0 

Media in the device :
DBT_DEVICEARRIVE/REMOVE::dbch_devicetype=2::DBTF_MEDIA=1 
DBT_DEVICEARRIVE/REMOVE::dbch_devicetype=2::DBTF_MEDIA=1 

However, I was wondering if it was also possible to filter on device
class basis (e.g. GUID_DEVINTERFACE_CDROM). I've tried various
combinations with the RegisterDeviceNotification() but am unable
accomplish this behaviour. 

Any hints on this are welcome...

void __fastcall TMainForm::WndProc(TMessage& Message) 
{ 
 if (Message.Msg==WM_DEVICECHANGE) 
 { 
  if((Message.WParam==DBT_DEVICEARRIVAL)|| 
   (Message.WParam==DBT_DEVICEREMOVECOMPLETE)) 
  { 
   PDEV_BROADCAST_HDR pDBHdr=(PDEV_BROADCAST_HDR)Message.LParam; 
   PDEV_BROADCAST_VOLUME lpdbv=(PDEV_BROADCAST_VOLUME)Message.LParam; 


DebugText("DBT_DEVICEARRIVE/REMOVE::dbch_devicetype=%X::DBTF_MEDIA=%X",
pDBHdr->dbch_devicetype, 
    lpdbv->dbcv_flags&DBTF_MEDIA 
    ); 
   if (!lpdbv->dbcv_flags&DBTF_MEDIA) 
   { 
    DebugText(">> Refresh Device Grid"); 
   } 
  } 
 } 
 else 
 { 
  TForm::WndProc(Message); 
 } 
} 

I tried several varation on this code :

void TMainForm::RegisterForDeviceNotification(void) 
{ 
 HDEVNOTIFY hDevNotify; 
 DEV_BROADCAST_DEVICEINTERFACE NotificationFilter; 
 GUID InterfaceClassGuid=GUID_DEVINTERFACE_CDROM; 

 ZeroMemory(&NotificationFilter,sizeof(NotificationFilter)); 
 NotificationFilter.dbcc_size=sizeof(DEV_BROADCAST_DEVICEINTERFACE); 
 NotificationFilter.dbcc_devicetype=DBT_DEVTYP_DEVICEINTERFACE; 
 NotificationFilter.dbcc_classguid=InterfaceClassGuid; 

 hDevNotify=RegisterDeviceNotification( 
      Application->Handle, 
      &NotificationFilter, 
      DEVICE_NOTIFY_WINDOW_HANDLE); 

 if(hDevNotify) 
 { 

MainForm->DebugText("RegisterDeviceNotification(GUID_DEVINTERFACE_CDROM)
: OK"); 
 } 
 else 
 { 
  MainForm->DebugText("RegisterDeviceNotification
(GUID_DEVINTERFACE_CDROM) : ERROR"); 
 } 
}