Positioning of an error trap

Mudface · Mar 10th, 2002, 06:28 AM

I have a fairly lengthy routine which seems to be fairly tight, but unfortunately will be used by our QC dept, who can break almost anything

. The main part of the routine looks similar to this: -

Public Sub Main()

Call Sub1
Call Sub2
Call Sub3
call Sub4

End Sub

If I wrap an error trap around the above, will any errors thrown up in the called subs be caught by it? Or do I need a separate trap within each sub?

Thanks for any help.

Mar 10th, 2002, 06:42 AM

[quote]
I have a fairly lengthy routine which seems to be fairly tight, but unfortunately will be used by our QC dept, who can break almost anything . The main part of the routine looks similar to this: -

Public Sub Main()

Call Sub1
Call Sub2
Call Sub3
call Sub4

End Sub

If I wrap an error trap around the above, will any errors thrown up in the called subs be caught by it? Or do I need a separate trap within each sub?

Thanks for any help.

[quote]

Hi Mudface,

The answer to your question is yes. If Sub Main has an error handling statement and an error occurs in Sub1 the error will be handled in Sub Main. However, if you have a statement in Sub1 which handles errors then that will take priority over the one in Sub Main. Another point worth bearing in mind is that if in Sub1 you have a line like On Error Goto ErrSub1 but then later you use On Error Goto 0 error handling will be return to Sub Main or whatever sub called Sub1.

If you set a breakpoint on Proc2 and step through this code you'll see what I mean.

HTH,
Dan.

Code:

Sub Main()
On Error GoTo errHandler

Proc2

Exit Sub
errHandler:
MsgBox "Error " & Err.Description

End Sub


Sub Proc2()
On Error GoTo errhndle
Dim x As Long

x = 1 / 0

On Error GoTo 0

x = 1 / 0

errhndle:

MsgBox "Error in proc2"

Resume Next
End Sub

dk · Mar 10th, 2002, 06:44 AM

BTW, that was me - it's too early on a Sunday to be doing this

Regards,
Dan

Mudface · Mar 10th, 2002, 06:50 AM

Thanks Dan, that'll save a fair bit of typing, I just wanted something simple to show there had been an error and that I should be notified, rather than having the user dumped out unceremoniously.

I was going to try and raise errors within each of the subs and see what happened, but forgot to bring the file home with me

.

Early?! Not when you've been up since 4 with a 4 month old with a cold...

[ This Message was edited by: Mudface on 2002-03-10 05:51 ]

Mar 10th, 2002, 06:42 AM	#2
Guest Posts: n/a	[quote] I have a fairly lengthy routine which seems to be fairly tight, but unfortunately will be used by our QC dept, who can break almost anything . The main part of the routine looks similar to this: - Public Sub Main() Call Sub1 Call Sub2 Call Sub3 call Sub4 End Sub If I wrap an error trap around the above, will any errors thrown up in the called subs be caught by it? Or do I need a separate trap within each sub? Thanks for any help. [quote] Hi Mudface, The answer to your question is yes. If Sub Main has an error handling statement and an error occurs in Sub1 the error will be handled in Sub Main. However, if you have a statement in Sub1 which handles errors then that will take priority over the one in Sub Main. Another point worth bearing in mind is that if in Sub1 you have a line like On Error Goto ErrSub1 but then later you use On Error Goto 0 error handling will be return to Sub Main or whatever sub called Sub1. If you set a breakpoint on Proc2 and step through this code you'll see what I mean. HTH, Dan. Code: Sub Main() On Error GoTo errHandler Proc2 Exit Sub errHandler: MsgBox "Error " & Err.Description End Sub Sub Proc2() On Error GoTo errhndle Dim x As Long x = 1 / 0 On Error GoTo 0 x = 1 / 0 errhndle: MsgBox "Error in proc2" Resume Next End Sub

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Mar 10th, 2002, 06:28 AM	#1
Mudface MrExcel MVP Join Date: Feb 2002 Location: Sunny, spring-like Hull Posts: 3,339	I have a fairly lengthy routine which seems to be fairly tight, but unfortunately will be used by our QC dept, who can break almost anything . The main part of the routine looks similar to this: - Public Sub Main() Call Sub1 Call Sub2 Call Sub3 call Sub4 End Sub If I wrap an error trap around the above, will any errors thrown up in the called subs be caught by it? Or do I need a separate trap within each sub? Thanks for any help.

Mar 10th, 2002, 06:44 AM	#3
dk MrExcel MVP Join Date: Feb 2002 Location: Sydney, Australia Posts: 2,908	BTW, that was me - it's too early on a Sunday to be doing this Regards, Dan

Mar 10th, 2002, 06:50 AM	#4
Mudface MrExcel MVP Join Date: Feb 2002 Location: Sunny, spring-like Hull Posts: 3,339	Thanks Dan, that'll save a fair bit of typing, I just wanted something simple to show there had been an error and that I should be notified, rather than having the user dumped out unceremoniously. I was going to try and raise errors within each of the subs and see what happened, but forgot to bring the file home with me . Early?! Not when you've been up since 4 with a 4 month old with a cold... [ This Message was edited by: Mudface on 2002-03-10 05:51 ]