simple error

Hi. I'm stepping through a record set from a database, such as in the following code:

Code:

---

oRS.MoveFirst
 Do while NOT oRS.eof
  Dim fx as string
  fx = oRS("FaxNumber")
  oRS.MoveNext
 Loop
 oRS.Close

---

But in my database some of the faxnumber fields are empty. This is causing the following error:

"Runtime error 94: Invalid use of null"

I tried putting an if statement like

Code:

---

if oRS("FaxNumber") is NOT NULL then..

---

but that didn't work, for the same reasons...

I don't know enough about VB to know how to handle this... seems this worked fine when I did it in ASP...

tx
d8

string variables don't like being set to null, same for text boxes. it can be a pain. the easiest way i've found for getting round it is: -

if isnull(oRS("FaxNumber")) = false then
fx = oRS("FaxNumber")
oRS.MoveNext
Loop
oRS.Close

i don't know why 'is not null' and '<> null' don't work. maybe someone out there who knows could explain it....

Hey dvst

This is a normal problem that everyone struggles thorugh when doing database work for the first time. Here is a quick peice of code that I wrote that illeviates that problem:

Code:

---

Function strClean(pvarString As Variant) As String

    If IsNull(pvarString) Or IsEmpty(pvarString) Then
        strClean = ""
        Exit Function
    End If
   
    strClean = Trim(CStr(pvarString))

End Function

---

Use it like this:

Code:

---

    oRS.MoveFirst
    Do While NOT oRS.EOF
        Dim fx as string
        fx = strClean(oRS!FaxNumber)
        oRS.MoveNext
    Loop
    oRS.Close

---

Hope this helps!

thanks jimbob, and skippy!

skippy: nice work with that code! I'm implementing it!!
tx