VB3 How to Get or Create a Unique Audio CD Volume Label (112768)

MORE INFORMATION

In order to retrieve the unique volume identifier from the CD, you need to call MSCDEX directly. The information on how to do this is contained within the MSCDEX 2.20 specification.

Because some manufacturers aren't including this unique identifier on their CDs, Microsoft recommends that you create a unique volume identifying number based on the track information already included on the CD. The following example shows you how.

Step-by-Step Example

This example shows a method for creating a unique number to identify an audio CD based on track information. The purpose of this number is to make it possible for Visual Basic programs to recognize a loaded CD and retrieve information from it.

1. Start a new project in Visual Basic. Form1 is created by default.
2. Add a text box (Text1) and an MCI control (MMControl1) to Form1.
3. Place the following code in the Form_Load event of Form1:

      Sub Form_Load ()
         Dim DiskID As Long
         Dim Track As Integer
         ' Initialize CD:
         mmcontrol1.DeviceType = "CDAudio"
         mmcontrol1.Command = "open"
         ' Make unique number based on tracks and tracklength:
         DiskID = mmcontrol1.Tracks
         For Track = 1 To mmcontrol1.Tracks
            mmcontrol1.Track = Track
            DiskID = DiskID + mmcontrol1.TrackLength  ' Add 4-byte TrackLength
            DiskID = DiskID + mmcontrol1.Length       ' Add 4-byte CD Length
         Next Track
         ' Set text to unique value:
         Text1.Text = DiskID
      End Sub
   						

4. Load a CD.
5. Start the program, or press the F5 key.
6. The Text1 box should have a unique identifying number for the CD.

NOTE: Before starting the program, a CD must be inserted and ready to play. Therefore, you should add code to detect when a CD has been inserted and then run the above code.