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vbams-accesserror-handling

Automatically generating handling of issues

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.

Solution

  • My solution is the following:

    1. install MZ-Tools, a very interesting add-on for VBA. No they did not pay me to write this. Version 3 was free, but since version 8.0, the add-in is commercially sold.
    2. 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 a hidden and undocumented function in the VBA standard library, '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:

    1. display it as a message on the screen
    2. Automatically insert a line in an error log file with the description of the error or
    3. 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?