The following example illustrates use of the hEnv property when accessing an ODBC API function. This code displays all registered data source names (DSNs) in a ListBox control.
Private Sub ShowDSNs_Click()
Dim fDirection As Integer
Dim szDSN As String * 1024
Dim cbDSNMax As Integer
Dim pcbDSN As Integer
Dim szDescription As String * 1024
Dim cbDescriptionMax As Integer
Dim pcbDescription As Integer
Dim Item As String
Set En = rdoEnvironments(0)
fDirection = SQL_FETCH_NEXT
cbDSNMax = 1023
cbDescriptionMax = 1023
List1.Clear
I = SQL_SUCCESS
While I = SQL_SUCCESS
szDSN = String(1024, " ")
szDescription = String(1024, " ")
I = SQLDataSources(En.hEnv, fDirection, szDSN, _
cbDSNMax, pcbDSN, szDescription, _
cbDescriptionMax, pcbDescription)
Item = Left(szDSN, pcbDSN) & " - " _
& Left(szDescription, pcbDescription)
Debug.Print Item
List1.AddItem Item
Wend
End Sub