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Getting Device List From Device Manager With Setupapi

I had need to figure out which COM port a USB-serial converter was installed as. If you looked under Device Manager, it was easy to tell from the names. First I tried EnumPorts, but that just gave me the COM number and 'Local Port'. I tried using the WMI, but the device I was looking for was the one that it wouldn't list for some reason. (Worked fine for my other virtual COM port USB device.) So I stumbled onto the setupapi library, but there was no VB examples, only some C. So through some trial and error, I devised a DeviceLister VB6 class to get names and descriptions of devices. It could be changed to include more, but I stopped at names/descriptions.

By five-cent example returns a list of 'Ports' devices (your results will vary):
ECP Printer Port (LPT1)
Communications Port (COM1)
Digi PKG-U Serial Port Adapter (COM16)
^-that last one was the sucker I was after

I thought 'Hey I wonder if anyone else would be looking for this?' so I post it here. It's not the prettiest implementation, but might be a starting point for someone.

Note: The MSDN seems to indicate that this only works for Win2k and beyond.

EDIT: I added an example of retrieving all devices. Also I setup an option to list devices that are not present. Now I can see ports that were installed but aren't active.

Edited by - FD 80 on 6/20/2008 11:35:57 AM

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I'm making an application where the user initially loads an image using a CommonFileDialog box.Creating a DC I can paint this onto a picture control. Then the user using his mouse is clicking on the image to select the area he is interested in and I have it displayed onto the picture alone,then he can zoom it e.t.c. register control points e.t.c.
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Part of the code within a sub i use to store the selection:

'trying to debug Device Context problem cause final output still displays orginal BMP transparent background or DC is not updated of the current display on screen

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'show selection
Call Array2Picture(1) 'ingore this bit,displays the array back to picture
ProgressBar1.Visible = False
statusText = "Ready"
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ProgressBar1.Value = 0

'DC once I have new content i though I would update the DC like this
lngDC = CreateCompatibleDC(Picture1.hdc)
lngOrigBMP = SelectObject(lngDC, stdPic.Handle)'this is used when loading the original BMP too

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I imagine that I can't also pass arrays to DC directly.
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I found this function that is exaclty what im looking for, however one of the parameteres says the input is a "Device to Draw on" As Type Long. How would I go about getting an object as this decive sush as Form1.

' DrawGradient (FUNCTION)
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' hDC - The device to draw on
' Top - Distance in pixels, from top
' Left - Distance in pixels, from left
' Width - In pixels
' Height - In pixels
' colourTopLeft - The colour of the top-left corner
' colourTopRight - The colour of the top-right corner
' colourBottomLeft - The colour of the bottom-left corner
' colourBottomRight - The colour of the bottom-right corner
Public Function DrawGradient(hDC As Long, Left As Long, Top As Long, Width As Long, Height As Long, colourTopLeft As Long, colourTopRight As Long, colourBottomLeft As Long, colourBottomRight As Long)


End Function

...could Not Connect To The Device....
Hi all !

I am trying now for 3 days to program my "typhoon myguide pocket pc" with embedded visual basic, without any success : if VB tries to connect to the pocket pc, I get :
The platform manager could not connect to the device.
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project type does not match to the connected device,
or if a required file in
Windows CE Services or the platform SDK is missing or corrupt.
(Error code=0xLX)

The connection (active sync) is working, I can easily transfer files to the pocket pc.
The selected platform in embVB is Pocket PC 2002 (Default Device), my Pocket PC uses Microsoft Pocket PC, Version 4.20.1081.
I dont use any german pathnames (a known bug of embedded VB, which I found on the MS homepage).
Is there anyone, who had the same problem and solved it ????
I would be glad, if someone could help me !!!

thanks, Joerg

How To Detect A USB Device?
Hi guys

Im trying to write the code for my VB program that detects a USB device, in this case a USB camera, does anyone have any suggestions? tips or what have ya

Thanks for answering, much appreciated

About Device Contexts
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is this possible? please help

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