Public Function QueryCapability( _
   ByVal type As TwainCapabilityType _
) As TwainCapability

Dim instance As TwainSession
Dim type As TwainCapabilityType
Dim value As TwainCapability
 
value = instance.QueryCapability(type)

public TwainCapability QueryCapability( 
   TwainCapabilityType type
)

public:
TwainCapability^ QueryCapability( 
   TwainCapabilityType type
) 

Public Sub QueryCapabilityExample(ByVal parent As IWin32Window)
   Try
      Dim twnSession As TwainSession = New TwainSession()
      twnSession.Startup(parent, "manufacturer", "productFamily", "version", "application", TwainStartupFlags.None)

      Dim twCap As TwainCapability = twnSession.QueryCapability(TwainCapabilityType.ImageUnits)

      If twCap.Information.ContainerType = TwainContainerType.OneValue Then
         If CType(twCap.OneValueCapability.Value, TwainCapabilityValue) <> TwainCapabilityValue.UnitInches Then
            twCap.OneValueCapability.Value = TwainCapabilityValue.UnitInches
            twnSession.SetCapability(twCap, TwainSetCapabilityMode.Set)
         End If
      End If
      twnSession.Shutdown()
   Catch ex As Exception
      MessageBox.Show(ex.Message)
   End Try
End Sub

public void QueryCapabilityExample(IWin32Window parent)
{
   try
   {
      TwainSession twnSession = new TwainSession();
      twnSession.Startup(parent, "manufacturer", "productFamily", "version", "application", TwainStartupFlags.None);

      TwainCapability twCap = twnSession.QueryCapability(TwainCapabilityType.ImageUnits);

      if (twCap.Information.ContainerType == TwainContainerType.OneValue)
      {
         if (twCap.OneValueCapability.Value != (object)TwainCapabilityValue.UnitInches)
         {
            twCap.OneValueCapability.Value = TwainCapabilityValue.UnitInches;
            twnSession.SetCapability(twCap, TwainSetCapabilityMode.Set);
         }
      }
      twnSession.Shutdown();
   }
   catch (Exception ex)
   {
      MessageBox.Show(ex.Message);
   }
}