How to get useful Windows device information in VBA

Here are (at least) 3 properties of hardware like hard disks (whether they are HDD, SSD, USB or else), printers or anything else that Windows considers a device. These can be very useful to obtain in applications that manage enterprise assets like data and documents:

These hardware properties allow us to uniquely an reliably identify a physical device.

Unfortunately, they’re not so easy to obtain. Particularly if we develop our applications with the “high level” languages that we use in database management systems like Microsoft Access (but also WinDev or FileMaker to name a few others), or in development environments that do not have the necessary, production ready, components or libraries to interact with the system.

Then there are different technologies we can use to get to these hardware properties, like:

So, let’s start at the end (!), because we want to get into action immediately, don’t we ?
Some explanation will follow later in this post.

Just before jumping there, let me point out where I am going with all this stuff next:

Watch the (short) demo video

Get device information from an access database demo


Some (quick) explanation

We can see the VB/A declarations that import the DLL functions in the declarations section of the MDeviceInfo.bas module:

Get to one API function

Instead of crippling our code with calls to each of the DLL functions, we can create one single function that does it all:

This way, we don’t have to worry about forgetting to call the DICreateDeviceInfo() and DIDestroyDeviceInfo() functions that are necessary for the DLL to do its job without crashes.

We gather the retrieved device information in an easy to access structure, in the following (public) Type definition:

Another way of doing it is using a class module. We’ll do that in the next post, where we set up the ActiveX OOP EXE server that will notify us of the devices arrival/removal in real time.

Sample usage

Take a look at the demo() procedure in the MMain.bas module:

Anyway, if you made it thru here, thank for your attention, don’t hesitate to share a link to this post where you see fit, open or join the conversation here, or drop me a tweet (I’m @francescofoti), I’ll always appreciate that.

And see you soon, because we’re not done yet 😉