hi Jim,
Jim Franklin wrote:
[Quoted Text] > Can anyone tell me if it is possible to determine which device is being used
> when I have two input devices?
Yes, it's possible. But it is really hardcore system programming which
needs imho a kernel driver to intercept the messages.
> I have an Access 2003 app being used on a
> Windows XP pc with a magnetic key reader which sends a number of keystrokes
> to the app when a key is tapped on it (the sort of thing barstaff use at the
> till in pubs & clubs etc.)
Why do you need to know that?
You can configure most readers to append an extra start and stop
character, eg. STX/ETX. You can use these as criteria in your
application using the Key Press event and Key Preview, e.g. from a
barcode scanner:
Option Compare Database
Option Explicit
Private m_BarcodeScanning As Boolean
Private m_BarcodeString As String
Public Sub Barcode(ABarcode As String)
' Do Barcode Magic Here:
txtBarCode.Value = ABarcode
End Sub
Private Sub Form_Current()
m_BarcodeScanning = False
End Sub
Private Sub Form_KeyPress(KeyAscii As Integer)
On Local Error GoTo LocalError
' Start Transmission STX
If KeyAscii = 2 Then
KeyAscii = 0
m_BarcodeScanning = True
m_BarcodeString = ""
End If
' End Transmission ETX
If KeyAscii = 3 Then
KeyAscii = 0
m_BarcodeScanning = False
' Weiterbearbeitung
Barcode m_BarcodeString
End If
If m_BarcodeScanning And (KeyAscii > 0) Then
m_BarcodeString = m_BarcodeString & Chr$(KeyAscii)
KeyAscii = 0
End If
Exit Sub
LocalError:
m_BarcodeScanning = False
m_BarcodeString = ""
End Sub
mfG
--> stefan <--
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