'Puts a single field from a recordset in a collection
'Parameters: rs: the recordset, Valname: The name or position of the field, KeyName (optional): the name or position of the field you want to use as keys in the collection
'Usage: Set MyCollection = RSToColl(MyRS, "Field1")
Public Function RSToColl(rs As DAO.Recordset, Optional ValName As Variant = 0, Optional KeyName As Variant = Null) As VBA.Collection
    Dim coll As New VBA.Collection
    If Not rs.EOF Or rs.RecordCount > 0 Then rs.MoveFirst
    Do While Not rs.EOF
        If IsNull(KeyName) Then
            coll.Add rs.Fields(ValName).Value
        Else
            coll.Add rs.Fields(ValName).Value, rs.Fields(KeyName).Value & ""
        End If
        rs.MoveNext
    Loop
    Set RSToColl = coll
End Function