We really like the @IsValid formula to check to see if a document is valid before performing another operation, but sometimes we're not using formula language, so a script equivalent is needed.

When writing script and you want to find out if the current document has any validation errors, use this code:

Dim ws As New NotesUIWorkspace
Dim uidoc As NotesUIDocument

Set uidoc = ws.CurrentDocument
On Error Resume Next ' Trap errors
Call uidoc.Refresh
On Error Goto 0 ' Reset the error handler
If Err <> 0 Then
   Err = 0 ' Clear it, or else next time it will be set even if there is not an error
   Exit Sub ' Exit out since the validation failed
End If
' ... continue with your code