Public Sub QueryFileSystem( _
   ByVal fileSystem As TwainFileSystem, _
   ByVal message As TwainFileSystemMessage _
) 

Dim instance As TwainSession
Dim fileSystem As TwainFileSystem
Dim message As TwainFileSystemMessage
 
instance.QueryFileSystem(fileSystem, message)

public void QueryFileSystem( 
   TwainFileSystem fileSystem,
   TwainFileSystemMessage message
)

public:
void QueryFileSystem( 
   TwainFileSystem^ fileSystem,
   TwainFileSystemMessage message
) 

Public Sub QueryFileSystemExample(ByVal parent As IWin32Window)
   Dim session As TwainSession = New TwainSession()
   Dim fileSystem As TwainFileSystem = New TwainFileSystem()
   Dim msg As String

   Try
      session.Startup(parent, "manufacturer", "productFamily", "version", "application", TwainStartupFlags.None)
      session.QueryFileSystem(fileSystem, TwainFileSystemMessage.AutomaticCaptureDirectory)

      ' I changed the following line from "fileSystem.FileType" to "fileSystem.FileFormat"
      msg = String.Format("Input Name = {0}" & Constants.vbLf & "Output Name = {1}" & Constants.vbLf & "Recursive = {2}" & Constants.vbLf & "FileType = {3}" & Constants.vbLf & "FileSize = {4}" & Constants.vbLf & "CreateTimeDate = {5}" & Constants.vbLf & "ModifiedTimeDate = {6}" & Constants.vbLf & "FreeMediaSpace = {7}" & Constants.vbLf & "NewImageSize = {8}" & Constants.vbLf & "NumberOfFiles = {9}" & Constants.vbLf & "NumberOfAudioSnippets = {10}" & Constants.vbLf & "DeviceGroupMask = {11}" & Constants.vbLf, fileSystem.InputName, fileSystem.OutputName, fileSystem.Recursive, fileSystem.FileFormat, fileSystem.FileSize, fileSystem.CreateTimeDate, fileSystem.ModifiedTimeDate, fileSystem.FreeSpace, fileSystem.NewImageSize, fileSystem.NumberOfFiles, fileSystem.NumberOfAudioSnippets, fileSystem.DeviceGroupMask)

      MessageBox.Show(msg)
   Catch ex As Exception
      MessageBox.Show(ex.Message)
   Finally
      session.Shutdown()
   End Try
End Sub

public void QueryFileSystemExample(IWin32Window parent)
{
   TwainSession session = new TwainSession();
   TwainFileSystem fileSystem = new TwainFileSystem();
   string msg;

   try
   {
      session.Startup(parent, "manufacturer", "productFamily", "version", "application", TwainStartupFlags.None);
      session.QueryFileSystem(fileSystem, TwainFileSystemMessage.AutomaticCaptureDirectory);

      msg = String.Format("Input Name = {0}\nOutput Name = {1}\nRecursive = {2}\nFileType = {3}\nFileSize = {4}\nCreateTimeDate = {5}\nModifiedTimeDate = {6}\nFreeMediaSpace = {7}\nNewImageSize = {8}\nNumberOfFiles = {9}\nNumberOfAudioSnippets = {10}\nDeviceGroupMask = {11}\n",
         fileSystem.InputName,
         fileSystem.OutputName,
         fileSystem.Recursive,
         // I changed the following line from "fileSystem.FileType" to "fileSystem.FileFormat"
         fileSystem.FileFormat,
         fileSystem.FileSize,
         fileSystem.CreateTimeDate,
         fileSystem.ModifiedTimeDate,
         fileSystem.FreeSpace,
         fileSystem.NewImageSize,
         fileSystem.NumberOfFiles,
         fileSystem.NumberOfAudioSnippets,
         fileSystem.DeviceGroupMask);

      MessageBox.Show(msg);
   }
   catch (Exception ex)
   {
      MessageBox.Show(ex.Message);
   }
   finally
   {
      session.Shutdown();
   }
}