This is more an observation than a real question: MS-Access (and VBA in general) is desperately missing a tool where error handling code can be generated automatically, and where the line number can be displayed when an error occurs. Did you find a solution? What is it? I just realized how many hundreds of hours I spared since I found the right answer to this basic problem a few years ago, and I'd like to see what are your ideas and solutions on this very important issue.
Well there are a couple of tools that will do what you ask MZ Tools and FMS Inc come to mind.
Basically they involve adding an:
On Error GoTo ErrorHandler
to the top of each proc and at the end they put an:
ErrorHandler:
Call MyErrorhandler Err.Number, Err.Description, Err.LineNumber
label with usually a call to a global error handler where you can display and log custom error messages
My solution is the following:
- install MZ-Tools, a very interesting add-on for VBA. No they did not pay me, anyway it is free.
- program a standard error handler code such as this one (see MZ tools menu/Options/Error handler):
On Error GoTo {PROCEDURE_NAME}_Error
{PROCEDURE_BODY}
On Error GoTo 0
Exit {PROCEDURE_TYPE}
{PROCEDURE_NAME}_Error:
debug.print "#" & Err.Number, Err.description, "l#" & erl, "{PROCEDURE_NAME}", "{MODULE_NAME}"
This standard error code can be then automatically added to all of your procs and function by clicking on the corresponding button in the MZ-Tools menu. You'll notice that we refer here to an undocumented value/property of VBA (2003 edition), 'erl', which stands for 'error line'. You got it! If you ask MZ-Tools to automatically number your lines of code, 'erl' will then give you the number of the line where the error occured. You will have a complete description of the error in your immediate window, such as:
#91, Object variable or With block variable not set, l# 30, addNewField, Utilities
Of course, once you realize the interest of the system, you can think of a more sophisticated error handler, that will not only display the data in the debug window but will also:
- display it as a message on the screen
- Automatically insert a line in an error log file with the description of the error or
- if you are working with Access or if you are connected to a database, automatically add a record to a Tbl_Error table!
meaning that each error generated at the user level can be stored either in a file or a table, somewhere on the machine or the network. Are we talking about building an automated error reporting system working with VBA?
What about using "Erl", it will display the last label before the error (e.g., 10, 20, or 30)?
Private Sub mySUB()
On Error GoTo Err_mySUB
10:
Dim stDocName As String
Dim stLinkCriteria As String
20:
stDocName = "MyDoc"
30:
DoCmd.openform stDocName, acFormDS, , stLinkCriteria
Exit_mySUB:
Exit Sub
Err_mySUB:
MsgBox Err.Number & ": " & Err.Description & " (" & Erl & ")"
Resume Exit_mySUB
End Sub