Hi,

I'm looking for a way of checking whether a specific USB device (a
webcam) is plugged in. I have the Vendor and Product ID numbers for the
device.

I found an article (http://www.vsj.co.uk/articles/display.asp?id=600)
with code sample that does the trick for human input devices (mouse,
keyboard, ...) but am struggling for my webcam.

Any help appreciated, thanks.

Gary

"beaker" <(E-Mail Removed)> wrote in message
news:OxQQ%(E-Mail Removed)...
>
> Hi,
>
> I'm looking for a way of checking whether a specific USB device (a webcam)
> is plugged in. I have the Vendor and Product ID numbers for the device.
>
> I found an article (http://www.vsj.co.uk/articles/display.asp?id=600) with
> code sample that does the trick for human input devices (mouse, keyboard,
> ...) but am struggling for my webcam.
>
> Any help appreciated, thanks.
>
> Gary

Gary,

It's easy outside of .NET if you handle the WM_DEVICECHANGE message. Below
is a snippet of a MFC program that does that. It shouldn't be hard to map
this to .NET, here's a discussion of just that, I haven't tried it myself:

http://www.codecomments.com/archive2...-4-185490.html

My MFC (edited) code snippet:

BOOL CConfigWinDlg::OnDeviceChange(UINT nEventType, DWORD_PTR dwData)
{
DEV_BROADCAST_DEVICEINTERFACE *devInterface;
DEV_BROADCAST_HDR *brHeader = (DEV_BROADCAST_HDR *)dwData;

switch (nEventType)
{
case (DBT_DEVICEARRIVAL):
if (brHeader && brHeader->dbch_devicetype == DBT_DEVTYP_DEVICEINTERFACE)
{
devInterface = (DEV_BROADCAST_DEVICEINTERFACE *)brHeader;
if (strstr(strupr(devInterface->dbcc_name), "VID_0403&PID_6006"))
{
// my device plugged in
// do something cool
}
else
{
// some other device plugged in
}
}
else
{
// unknown device plugged in
}
}
break;

// other cases
}
[snip]

andrew queisser wrote:
> "beaker" <(E-Mail Removed)> wrote in message
> news:OxQQ%(E-Mail Removed)...
>
>>Hi,
>>
>>I'm looking for a way of checking whether a specific USB device (a webcam)
>>is plugged in. I have the Vendor and Product ID numbers for the device.
>>
>>I found an article (http://www.vsj.co.uk/articles/display.asp?id=600) with
>>code sample that does the trick for human input devices (mouse, keyboard,
>>...) but am struggling for my webcam.
>>
>>Any help appreciated, thanks.
>>
>>Gary
>
>
> Gary,
>
> It's easy outside of .NET if you handle the WM_DEVICECHANGE message. Below
> is a snippet of a MFC program that does that. It shouldn't be hard to map
> this to .NET, here's a discussion of just that, I haven't tried it myself:
>
> http://www.codecomments.com/archive2...-4-185490.html
>
> My MFC (edited) code snippet:
>
> BOOL CConfigWinDlg::OnDeviceChange(UINT nEventType, DWORD_PTR dwData)
> {
> DEV_BROADCAST_DEVICEINTERFACE *devInterface;
> DEV_BROADCAST_HDR *brHeader = (DEV_BROADCAST_HDR *)dwData;
>
> switch (nEventType)
> {
> case (DBT_DEVICEARRIVAL):
> if (brHeader && brHeader->dbch_devicetype == DBT_DEVTYP_DEVICEINTERFACE)
> {
> devInterface = (DEV_BROADCAST_DEVICEINTERFACE *)brHeader;
> if (strstr(strupr(devInterface->dbcc_name), "VID_0403&PID_6006"))
> {
> // my device plugged in
> // do something cool
> }
> else
> {
> // some other device plugged in
> }
> }
> else
> {
> // unknown device plugged in
> }
> }
> break;
>
> // other cases
> }
> [snip]
>
>


Thanks, the article you gave the link to does half of what I need, and I
can now detect when the device is plugged in - but I still need to know
if the device is present when my app starts (and so misses the
appropriate event for that method.)

Any ideas?

Thanks again.