Error handling

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Guest

I have a form whos source is a query with record number criteria. This way,
upon opening of the form, it asks for a record number. When the user puts in
a record that is not in the set, the error handler gives a message and
requerys, which prompts for the record number again. This works perfectly,
but only once. If the user inputs an invalid record a second time, it asks
to end or debug. It appears that rearranging the code does not change
anything. Any suggestions?
 
I have a form whos source is a query with record number criteria. This way,
upon opening of the form, it asks for a record number. When the user puts in
a record that is not in the set, the error handler gives a message and
requerys, which prompts for the record number again. This works perfectly,
but only once. If the user inputs an invalid record a second time, it asks
to end or debug. It appears that rearranging the code does not change
anything. Any suggestions?
Click to expand...

Could you please post your code?

I'd actually suggest using a Form control for the criteria, opening a
recordset, and seeing if its Recordcount is zero; and take appropriate
action if so.

John W. Vinson[MVP]
 
It's hard to say without seeing your code, but I'll have a guess.

If an error occurs while you are in an error handler, then it will be
treated as an unhandled error. Your error handler should execute a Resume
statement to return to some code outside the handler.

Are you using Resume? I suspect not. Your code should look something like
this:

On Error Goto ErrHandler
PromptForRecord:
' ask the user for a record number
' lookup record
' error occurs if no record found
' continue with form opening
ExitPoint:
Exit Sub
ErrHandler:
' display message
If <need to retyr> then Resume PromptForRecord
Resume ExitPoint
 
I am using goto instead of resume (but only because I am not familiar with
it), and I don't want to exit, as I am using this code on form load. This is
the code without the error handler, which works fine until I put in a
nonexistant loan number:

Private Sub Form_Load()
Begin:
If IsNull(Me.Lock) Then
Me.Lock = fosusername()
DoCmd.RunCommand acCmdSaveRecord
Else
MsgBox "This record is locked by " & UCase([Lock]) & ", please try
another loan."
Me.Requery
GoTo Begin
End If
End Sub
-------------------------------------
And since I wrote the the semi-functional Error code yesterday and
subsequently deleted it instead of copying it, I can't even rewrite it to
work as well as it was then. This is very nearly it, though - it's currently
failing the first time around:

Private Sub Form_Load()
Begin:
On Error GoTo ErrHand
If IsNull(Me.Lock) Then
Me.Lock = fosusername()
DoCmd.RunCommand acCmdSaveRecord
Else
MsgBox "This record is locked by " & UCase([Lock]) & ", please try
another loan."
Me.Requery
GoTo Begin
End If
Exit Sub
ErrHand:
MsgBox "This is not a valid loan number, please try again."
Me.Requery
GoTo Begin
End Sub

Thank you both for your suggestions, I will look into them.


Graham Mandeno said:
It's hard to say without seeing your code, but I'll have a guess.

If an error occurs while you are in an error handler, then it will be
treated as an unhandled error. Your error handler should execute a Resume
statement to return to some code outside the handler.

Are you using Resume? I suspect not. Your code should look something like
this:

On Error Goto ErrHandler
PromptForRecord:
' ask the user for a record number
' lookup record
' error occurs if no record found
' continue with form opening
ExitPoint:
Exit Sub
ErrHandler:
' display message
If <need to retyr> then Resume PromptForRecord
Resume ExitPoint
--
Good Luck!

Graham Mandeno [Access MVP]
Auckland, New Zealand


scojerroc said:
I have a form whos source is a query with record number criteria. This
way,
upon opening of the form, it asks for a record number. When the user puts
in
a record that is not in the set, the error handler gives a message and
requerys, which prompts for the record number again. This works
perfectly,
but only once. If the user inputs an invalid record a second time, it
asks
to end or debug. It appears that rearranging the code does not change
anything. Any suggestions?
Click to expand...
Click to expand...
 
The point is that once you start executing your error handler code, you have
moved to a new "stack level", rather like calling another procedure or
executing a GoSub command. While you are at that level, any error that
occurs will be unhandled.

If you do a GoTo Begin in your error handler code, you are still at the
error handling level. (GoTo simply does a branch and makes no change to the
call stack). To return to the level where the original error occurred, you
MUST execute a Resume.

So, instead of GoTo Begin, use Resume Begin.
--
Good Luck!

Graham Mandeno [Access MVP]
Auckland, New Zealand

scojerroc said:
I am using goto instead of resume (but only because I am not familiar with
it), and I don't want to exit, as I am using this code on form load. This
is
the code without the error handler, which works fine until I put in a
nonexistant loan number:

Private Sub Form_Load()
Begin:
If IsNull(Me.Lock) Then
Me.Lock = fosusername()
DoCmd.RunCommand acCmdSaveRecord
Else
MsgBox "This record is locked by " & UCase([Lock]) & ", please try
another loan."
Me.Requery
GoTo Begin
End If
End Sub
-------------------------------------
And since I wrote the the semi-functional Error code yesterday and
subsequently deleted it instead of copying it, I can't even rewrite it to
work as well as it was then. This is very nearly it, though - it's
currently
failing the first time around:

Private Sub Form_Load()
Begin:
On Error GoTo ErrHand
If IsNull(Me.Lock) Then
Me.Lock = fosusername()
DoCmd.RunCommand acCmdSaveRecord
Else
MsgBox "This record is locked by " & UCase([Lock]) & ", please try
another loan."
Me.Requery
GoTo Begin
End If
Exit Sub
ErrHand:
MsgBox "This is not a valid loan number, please try again."
Me.Requery
GoTo Begin
End Sub

Thank you both for your suggestions, I will look into them.


Graham Mandeno said:
It's hard to say without seeing your code, but I'll have a guess.

If an error occurs while you are in an error handler, then it will be
treated as an unhandled error. Your error handler should execute a
Resume
statement to return to some code outside the handler.

Are you using Resume? I suspect not. Your code should look something
like
this:

On Error Goto ErrHandler
PromptForRecord:
' ask the user for a record number
' lookup record
' error occurs if no record found
' continue with form opening
ExitPoint:
Exit Sub
ErrHandler:
' display message
If <need to retyr> then Resume PromptForRecord
Resume ExitPoint
--
Good Luck!

Graham Mandeno [Access MVP]
Auckland, New Zealand


scojerroc said:
I have a form whos source is a query with record number criteria. This
way,
upon opening of the form, it asks for a record number. When the user
puts
in
a record that is not in the set, the error handler gives a message and
requerys, which prompts for the record number again. This works
perfectly,
but only once. If the user inputs an invalid record a second time, it
asks
to end or debug. It appears that rearranging the code does not change
anything. Any suggestions?
Click to expand...
Click to expand...
Click to expand...
 
Graham Mandeno said:
The point is that once you start executing your error handler code, you have
moved to a new "stack level", rather like calling another procedure or
executing a GoSub command. While you are at that level, any error that
occurs will be unhandled.

If you do a GoTo Begin in your error handler code, you are still at the
error handling level. (GoTo simply does a branch and makes no change to the
call stack). To return to the level where the original error occurred, you
MUST execute a Resume.

So, instead of GoTo Begin, use Resume Begin.
Click to expand...


Excellent. Thank you, sir.
 
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