Check if object exists in VBScript

Question

I am using the HP ALM API to fetch a field from the database. The problem is that it can happend, that this field does not exist on the project, and everytime that happens, I get the error bellow.

How can I check the field object properly to make sure that I don't get this "Invalid customization field name" anymore?

Code:

Set field = custFields.Field("TEST", "TS_USER_88") <-- crashes here

label = field.UserLabel
If label = Null Then
    Print "[" & Sysdate() & "] Project can NOT be migrated..."
    Print "[" & Sysdate() & "] FIELD TS_USER_88 NOT FOUND - PROJECT IS NOT SUPPORTED."
Else
    ...
End If

Error:

xy.vbs(126, 7) (null): Invalid customization field name

Answer 1

You'll want to wrap your code in "On Error Resume Next", then handle the error.

On Error Resume Next
Set field = custFields.Field("TEST", "TS_USER_88")

If Err.Number <> 0 Then
  'Do Something to handle your error
  'stuff

  'Clear the error
  Err.Clear
End If
On Error Goto 0

'more stuff down here

Here's some more info on the Err object and some of it's properties:

http://msdn.microsoft.com/en-us/library/sbf5ze0e(v=vs.84).aspx