How do I read data from an xBase/Clipper file in VB6?

Question

• DBF file is in C:\dbase\clip53\PRG\stkmenu\WPACK3\
• DBF file is called WPACKS.CFG (deliberately not .DBF)

The VB6 code in an ActiveX EXE for opening the database and recordset:

Function OpenDatabase(sFile As Variant, Optional sProvider As Variant = "Provider=Microsoft.Jet.OLEDB.4.0") As Variant  ' ADODB.Connection
    Dim nErr As Long
    Dim sErr As String
    Dim oConnection As Object 'ADODB.Connection
    Set oConnection = CreateObject("ADODB.Connection")
    On Error Resume Next
    oConnection.open sProvider & ";Data Source=" & sFile
    nErr = Err.Number
    sErr = Err.Description
    On Error GoTo 0
    If nErr <> 0 Then
        Err.Raise OPENDATABASE_E_NOTFOUND, , sErr
    End If
    Set OpenDatabase = oConnection
End Function

Function OpenRecordSet(ByRef oDb As Variant, sQuery As Variant, Optional bCmdText As Boolean = False) As Variant ''ADODB.Connection ADODB.Recordset
    Const adOpenForwardOnly  As Long = 0
    Const adOpenStatic As Long = 3
    Const adOpenDynamic As Long = 2
    Const adOpenKeyset As Long = 1
    Const adLockOptimistic As Long = 3
    Const adCmdText As Long = 1
    Dim oRecordSet As Object 'ADODB.Recordset
    Set oRecordSet = CreateObject("ADODB.RecordSet")
    If bCmdText Then
        oRecordSet.open sQuery, , , adCmdText
    Else
        oRecordSet.open sQuery, oDb, adOpenKeyset, adLockOptimistic
    End If
    Set OpenRecordSet = oRecordSet
End Function

The script accessing these methods looks a little like VBScript. It is VBScript, but executed by the aforementioned ActiveX EXE which uses MSScript control and has a whole pile of objects which it can make available to the script engine. A kind of VBScript-on-steroids approach.

uses database
uses system
dim db
dim rs
set db = database.opendatabase("C:\dbase\clip53\PRG\stkmenu\WPACK3\","Provider=Microsoft.Jet.OLEDB.4.0;Extended Properties=dBase III;User ID=Admin;Password=")
set rs = database.openrecordset(db, "SELECT * FROM WPACKS.CFG",true)
system.consolewriteline rs.recordcount

My problem is that I keep getting The connection cannot be used to perform this operation. It is either closed or invalid in this context. when it hits the oRecordSet.open sQuery, , , adCmdText (which I got from a Microsoft site.)

'Tis a tad irritating.

Answer 1

try using the latest and greatest FoxPro driver.

Answer 2

The connection string I use when I need to connect a DBF file is usually something like:

"Driver={Microsoft dBase Driver (*.dbf)};dbq=<filePath>"

It works fine for me.