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Chip Pearson Chip Pearson is offline
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Default Returning text from Userdefined Functions


Would it be reasonable, after fixing
any errors in the userforms (so that Userform1.Show doesn't error out), to
set it back to "Break on Unhandled Errors"?


I wouldn't. No matter how fully one tests code, any non-trivial code can
blow up under some unforeseen (and untested) circumstance, no matter how
remote. I would leave error handling at "break in class" for easy debugging
down the road. There is no reason to change it back to "unhandled errors".


--
Cordially,
Chip Pearson
Microsoft MVP - Excel, 10 Years
Pearson Software Consulting
www.cpearson.com
(email on the web site)


"Zone" wrote in message
...
Chip, That's fantastic. Wish I had know about this years ago. Sure would
have made learning userforms easier. Would it be reasonable, after fixing
any errors in the userforms (so that Userform1.Show doesn't error out), to
set it back to "Break on Unhandled Errors"?
James
"Chip Pearson" wrote in message
...
Check in VBE: Tools / Options / General / Break on Unhandled Errors


As a general rule, you should choose "Break In Class Module", not "Break
On
Unhandled Errors". This difference becomes clear when you have an error
in
an object module. Suppose you have a UserForm with code like:

Private Sub UserForm_Initialize()
Me.Label1.Caption = CStr(1 / 0) ' Error
End Sub

an a code module with code like

Sub ShowTheForm()
UserForm1.Show
End Sub

If you have the error trapping set to "Break On Unhandled Errors", you
'll
set a run time error on the line of code

UserForm1.Show

But there really isn't an error with the Show method. However, if you set
error trapping to "Break In Class Module", you'll get an error on the
correct line of code:
Me.Label1.Caption = CStr(1 / 0)

If you didn't know the difference in error handling modes, you could
spend a
lot a valuable time trying to figure out what is wrong with the Show
method.


--
Cordially,
Chip Pearson
Microsoft MVP - Excel, 10 Years
Pearson Software Consulting
www.cpearson.com
(email on the web site)



"Luca Brasi" wrote in message
...
Check in VBE: Tools / Options / General / Break on Unhandled Errors


DagL wrote:
I have looked into this, but does not see any difference. The error is
not happening in an called routine, it is inside the UDF. I have an
erorr
handler paragraph that calls an central error handler function. The
return string from the central error handler function is set to bee the
return value of the UDF. I tried not to call the central error handler
function, and have a simple error handler paragraph within the UDF, but
the same result is happening.

I have the error handler inside the UDF, and as soon as the execution
goes into this, the return from the UDF is wrong. When the code runs
without error, the return string is correct. See the code example I
wrote
in my first post. My problem is actually as simple as this show. If the
execution enters the error handler paragraph, the UDF does not return
what I set it to do.

Regards DagL

"Mike H" wrote:

Hi

Because the error handler is called from the UDF it is subject to the
same limitations as the UDF so if there's an error in the called
routine
you aren't notified and simply get the VALUE error in the cell. Check
out the error handler it sounds very much like the error is within
that.

Mike

"DagL" wrote:

This is the cell where the function is called from. Sometimes the
string is returned correct, but when the code has been in an error
handler, the cell displays "#VALUE!"


"Mike H" wrote:

A UDF cannot change any cell other than the one it is called from.


"DagL" wrote:

Hello!

I have a user defined function to write data back to a database in
my
Excel sheet. I return a smal text to show the user if the function
was successful or not. When I set the return value of the function
in
regular code, it works fine. But, when something goes wrong, the
execution goes to an error handler, the function does not return
the
string I set anymore.

I have the code:


Public Function WriteData()
on error goto ErrorHandler

.
.
calculations
.
.

WriteData = "OK" 'This is returned
correct
to the cell

goto End

ErrorHandler:

WriteData = "Not OK" 'This returns #VALUE to the
cell

End:

End Function


Can someone tell me the reason of this behavior, and/or what I am
doing wrong?

Regards DagL