vbObjectError Not Working as Expected

[johnywhy]

Like I said, I usually just start my errors at 1000 and forget vbObjectError

It seems there may be native errors in the region you're using, in which case you are overlapping native numbers. See
https://exceldevelopmentplatform.blo...criptions.html

'Private Const ERROR_CANTOPEN As Long = 1011 ' The configuration registry key could not be opened.
'Private Const ERROR_SERVICE_REQUEST_TIMEOUT As Long = 1053 ' The service did not respond to the start or control request in a timely fashion.'Private Const ERROR_INVALID_PIXEL_FORMAT As Long = 2000 ' The pixel format is invalid.
'Private Const ERROR_BAD_DRIVER As Long = 2001 ' The specified driver is invalid.
'Private Const ERROR_INVALID_WINDOW_STYLE As Long = 2002 ' The window style or class attribute is invalid for this operation.

Update: I guess these are Windows errors, not Excel errors. So this might not affect VBA programming.

Iac, the solution i offered above allows to use native numbers without conflict.

I've never gotten an all-purpose error handler that I liked

Does this mean your example is a handler that you do, or don't like?

I suggest that severity is a different kind of information than type, and shouldn't share the same enum as you have:

Public Enum errCustomNumbers
    errUserCanceled = 1011
    errClickedPause = 1053
    errBad = 2000
    errVeryBad = 2001
    errReallyBad = 2002
End Enum

[Paul_Hossler]

Does this mean your example is a handler that you do, or don't like?

I suggest that severity is a different kind of information than type, and shouldn't share the same enum as you have:

1. I meant that I've never been able to get something like your sub GlobalHander to be the way I wanted. If it does work for you, that's great. I just usually have the error handling inside the sub and not call another sub since IMO that decreases response flexibility

2. I hadn't thought about a 'severity score' based on the error number (1000-1999 = mild, 2000-2999 = medium, 3000-3999 = sever) but that's not a bad idea

[johnywhy]

I hadn't thought about a 'severity score' based on the error number (1000-1999 = mild, 2000-2999 = medium, 3000-3999 = sever) but that's not a bad idea

Heh, not what i had in mind. I wouldn't combine two distinct pieces of information, if it can be avoided. Severity may be contextual. A corrupt workbook might be fatal for some apps, but ok to ignore and skip for other apps. I would have done:

Enum CustomErr
          UserCancel = vbObjectError
          UserPause
          ProtectedWorkbook
          CorruptWorkbook
          ShellError
End Enum


Enum ErrorSeverity
          Mild
          Medium
          Severe
End Enum

And then put Severity in Err.Description. Or maybe it could be And'ed or Or'd with error-number, and together put into Err.Number?

[johnywhy]

My solution does work, but i still have to add vbObjectError to my custom errors!

For some reason, my prior example of 11 and 53 worked ok, but passing 0 as error number fails. The raised error is lost, and a new Automation Error occurs:

Err.Raise 0, "Custom"

So, VB won't allow me to overlap native numbers (or certain ones, i guess), even if i specify source. Starting my numbering at vbObjectError works.

Enum CustomError
          UserCancel = vbObjectError
          UserPause
          ProtectedWorkbook
          CorruptWorkbook
          ShellError
End Enum

Since vbObjectError = -2147221504 , that means my numbering will start at -2147221504 and go up from there. No, i'm wrong, it's not a negative number, it's unsigned, i'm told. Somehow, -2147221504 = 513???

Using "Custom" as error-source to disambiguate the custom error number from native numbers maybe not even needed. Or rather, may be used to differentiate between different types of custom errors, but my custom numbers still can't overlap the native ones.

It seems it would have been better if VB allowed every app to define it's own error numbers (even overlapping ones) with a .Source disambiguator, but what do i know.

[Paul_Hossler]

Debug show vbObjectErrror is a Long

?vartype(vbObjectError) 3

Long (long integer) variables are stored as signed 32-bit (4-byte) numbers ranging in value from -2,147,483,648 to 2,147,483,647.

\


BUt, .... if you're not in a class module then you probably want to forget about vbObjectError

Required. Long integer that identifies the nature of the error. Visual Basic errors (both Visual Basic-defined and user-defined errors) are in the range 0–65535. The range 0–512 is reserved for system errors; the range 513–65535 is available for user-defined errors.

When setting the Number property to your own error code in a class module, you add your error code number to the vbObjectErrorconstant. For example, to generate the error number 513, assign vbObjectError + 513 to the Number property.

You could bit map if you didn't have too many errors

Option Explicit


Enum CustomErr
        UserCancel = 1
        UserPause = 2
        ProtectedWorkbook = 4
        CorruptWorkbook = 8
        ShellError = 16
End Enum




Enum ErrorSeverity
        Mild = 2 ^ 13
        Medium = 2 ^ 14
        Severe = 2 ^ 15
End Enum




Sub test()
    Dim sErr As String, sLvl As String
    On Error GoTo ErrHandle


'    Err.Raise UserCancel + Mild
'    Err.Raise UserCancel + Medium
'    Err.Raise UserCancel + Severe


    Err.Raise ShellError + Medium


    
    Exit Sub




ErrHandle:
    If (Err.Number And UserCancel) <> 0 Then
        sErr = "User Cancel"
    ElseIf (Err.Number And UserPause) <> 0 Then
        sErr = "User Pause"
    ElseIf (Err.Number And ProtectedWorkbook) <> 0 Then
        sErr = "Protected Workbook"
    ElseIf (Err.Number And CorruptWorkbook) <> 0 Then
        sErr = "Corrupt Workbook"
    ElseIf (Err.Number And ShellError) <> 0 Then
        sErr = "Shell Error"
    End If




    If (Err.Number And Mild) <> 0 Then
        sLvl = "Mild"
    ElseIf (Err.Number And Medium) <> 0 Then
        sLvl = "Medium"
    ElseIf (Err.Number And Severe) <> 0 Then
        sLvl = "Severe"
     End If


    
    MsgBox "Error was " & sErr & " with severity of " & sLvl
End Sub

[johnywhy]

Debug show vbObjectErrror is a Long

So, not unsigned?

"The values are not signed Longs, so none of this is about "negative" anything. These values are unsigned and 32 bits long (DWORD)."
https://www.vbforums.com/showthread....=1#post5538131

BUt, .... if you're not in a class module then you probably want to forget about vbObjectError

Question: Is there any drawback to using vbObjectError in a module?

News flash: My "Custom" source method actually does work. As long as there's no harm in re-using native error numbers, i CAN disambiguate with .Source. Just have to start the Enum at 1, not 0. Which means, my custom errors seem to work fine without using vbObjectError. Am i missing anything?

So now i have to choose:
- i can re-use native error numbers, and disambiguate by setting .Source to "Custom"
- or, avoid native numbers by starting my enum at vbObjectError

You could bit map...

...
        Medium = 2 ^ 14
        Severe = 2 ^ 15
...
        CorruptWorkbook = 8
        ShellError = 16
...
    On Error Goto ErrHandle    ' DID YOU FORGET THIS?
...
    If (Err.Number And UserCancel) <> 0 Then
        sErr = "User Cancel"
...
    If (Err.Number And Mild) <> 0 Then
        sLvl = "Mild"
...

wOW, niCE woRK!
Stealing

... if you didn't have too many errors

How many?

[johnywhy]

.

[Paul_Hossler]

I'm going by the MS documentation:

Long (long integer) variables are stored as signed 32-bit (4-byte) numbers ranging in value from -2,147,483,648 to 2,147,483,647.



Long integer that identifies the nature of the error. Visual Basic errors (both Visual Basic-defined and user-defined errors) are in the range 0–65535. The range 0–512 is reserved for system errors; the range 513–65535 is available for user-defined errors.

When setting the Number property to your own error code in a class module, you add your error code number to the vbObjectErrorconstant.

How many?

65535 = 2^16-1

I used the 3 high order bits to mark severity, so that leaves 12 or 13 error messages

On Error Goto ErrHandle ' DID YOU FORGET THIS?

Second line

[johnywhy]

65535 = 2^16-1
I used the 3 high order bits to mark severity, so that leaves 12 or 13 error messages

I would say that's not a useful solution for this application, but still useful for other things.

[Paul_Hossler]

2. I hadn't thought about a 'severity score' based on the error number (1000-1999 = mild, 2000-2999 = medium, 3000-3999 = sever) but that's not a bad idea

I'd think about this

[johnywhy]

If I'm using vbObjectError as recommended, how to compose a conditional which can determine if my error is native or custom?

Enum CustomEr
          LaidEgg = vbObjectError
          UserEaten
          Paused
          Cancelled
End Enum


Sub GlobalHandler
          If IsCustomErr Then MsgBox "Custom"
End Sub


Function IsCustomErr()As Boolean
ONE OF THESE?
          With Err
                    IsCustomErr = .Number < 0
                    IsCustomErr = .Number >= vbObjectError
                    IsCustomErr = (.Number >= vbObjectError) And (.Number < 0)
                    IsCustomErr = .Number Or vbObjectError
                    IsCustomErr = TwosComplement(.Number) Or TwosComplement(vbObjectError)
          End With
End Function

(also asked here)

[Paul_Hossler]

If I'm using vbObjectError as recommended, how to compose a conditional which can determine if my error is native or custom?

Well, TBH I don't think that you are using vbObjectError as recommended since the way I read the below, you only use vbObjectError in a class module and you don't seem to be using a class module

When setting the Number property to your own error code in a class module, you add your error code number to the vbObject Error constant.

Since 746 (attachment) seems to be the highest system error number used, I'd just keep my errors between 1000 and 9999. Anything below is Excel's, anything between is my custom

Visual Basic errors (both Visual Basic-defined and user-defined errors) are in the range 0–65535.

The range 0–512 is reserved for system errors;

the range 513–65535 is available for user-defined errors.

[johnywhy]

you don't seem to be using a class module

Let's assume i am.

My reading of the spec is that vbObjectError isn't required for modules, not that it's forbidden. Do you think i may overlap native numbers if i used vbObjectError for custom errors in modules?

Since 746 (attachment) seems to be the highest system error number used, I'd just keep my errors between 1000 and 9999. Anything below is Excel's, anything between is my custom

maybe, but i don't feel that's reliable. Also, i think the unsigned-int nature of error numbers may be relevant.

Hoping to find an algorithm based on vbObjectError, rather than a hardcoded range.

thx!

[Paul_Hossler]

Well, you can try this

Option Explicit


Enum CustomErr
    LaidEgg = vbObjectError + 100
    UserEaten = vbObjectError + 200
    Paused = vbObjectError + 300
    Cancelled = vbObjectError + 400
End Enum




Sub drv()


    On Error GoTo ErrHandler
    
    Err.Raise UserEaten, "Sub drv", "User Eaten Error"
    
    MsgBox 1 / 0


    Exit Sub
    
ErrHandler:
    GlobalHandler
    Resume Next
End Sub




Sub GlobalHandler()
    Dim E As Long
    
    E = Err.Number - vbObjectError  '   needed to avoid Overflow Error
    
    If (Err.Number < 0) Then
        MsgBox "Custom Error, 'Number' = " & E
        MsgBox Err.Description
    Else
        MsgBox Err.Description
    End If
End Sub