VBScript Error Handling in For Each loops [duplicate] - loops

Question

A colleague and I were trying to figure out a way of doing the equivalent of a "continue" statement within a VBScript "For/Next" loop.
Everywhere we looked we found people had no way to do this in VBScript without having nasty nestings, which is not an option for us since it is a quite big loop.
We came out with this idea. Would it work just as a "continue(to next iteration)"? Does anyone have any better workaround or improvement suggestion?
For i=1 to N
For workaroundloop = 1 to 1
[Code]
If Condition1 Then
Exit For
End If
[MoreCode]
If Condition2 Then
Exit For
End If
[MoreCode]
If Condition2 Then
Exit For
End If
[...]
Next
Next
Thanks for your comments

Answer 1

Your suggestion would work, but using a Do loop might be a little more readable.
This is actually an idiom in C - instead of using a goto, you can have a do { } while (0) loop with a break statement if you want to bail out of the construct early.
Dim i
For i = 0 To 10
Do
If i = 4 Then Exit Do
WScript.Echo i
Loop While False
Next
As crush suggests, it looks a little better if you remove the extra indentation level.
Dim i
For i = 0 To 10: Do
If i = 4 Then Exit Do
WScript.Echo i
Loop While False: Next

Answer 2

A solution I decided on involved the use of a boolean variable to track if the for loop should process its instructions or skip to the next iteration:
Dim continue
For Each item In collection
continue = True
If condition1 Then continue = False End If
If continue Then
'Do work
End If
Next
I found the nested loop solutions to be somewhat confusing readability wise. This method also has its own pitfalls since the loop doesn't immediately skip to the next iteration after encountering continue. It would be possible for a later condition to reverse the state of continue. It also has a secondary construct within the initial loop, and requires the declaration of an extra var.
Oh, VBScript...sigh.
Also, if you want to use the accepted answer, which isn't too bad readability wise, you could couple that with the use of : to merge the two loops into what appears to be one:
Dim i
For i = 0 To 10 : Do
If i = 4 Then Exit Do
WScript.Echo i
Loop While False : Next
I found it useful to eliminate the extra level of indentation.

Answer 3

One option would be to put all the code in the loop inside a Sub and then just return from that Sub when you want to "continue".
Not perfect, but I think it would be less confusing that the extra loop.

Answer 4

I use to use the Do, Loop a lot but I have started using a Sub or a Function that I could exit out of instead. It just seemed cleaner to me. If any variables you need are not global you will need to pass them to the Sub also.
For i=1 to N
DoWork i
Next
Sub DoWork(i)
[Code]
If Condition1 Then
Exit Sub
End If
[MoreCode]
If Condition2 Then
Exit Sub
End If
[MoreCode]
If Condition2 Then
Exit Sub
End If
[...]
End Sub

Answer 5

We can use a separate function for performing a continue statement work. suppose you have following problem:
for i=1 to 10
if(condition) then 'for loop body'
contionue
End If
Next
Here we will use a function call for for loop body:
for i=1 to 10
Call loopbody()
next
function loopbody()
if(condition) then 'for loop body'
Exit Function
End If
End Function
loop will continue for function exit statement....

Answer 6

I've always used an Do While loop. This works with both For type loops.
For iIndex = 0 to 100
Do
If bCondition then Exit Do
...
Loop While False
Next
IMHO, this just looks clean.
I just saw Crush's answer, at the bottom. Sorry for the duplicate answer.

Answer 7

Implement the iteration as a recursive function.
Function Iterate( i , N )
If i == N Then
Exit Function
End If
[Code]
If Condition1 Then
Call Iterate( i+1, N );
Exit Function
End If
[Code]
If Condition2 Then
Call Iterate( i+1, N );
Exit Function
End If
Call Iterate( i+1, N );
End Function
Start with a call to Iterate( 1, N )

Answer 8

Try use While/Wend and Do While / Loop statements...
i = 1
While i < N + 1
Do While true
[Code]
If Condition1 Then
Exit Do
End If
[MoreCode]
If Condition2 Then
Exit Do
End If
[...]
Exit Do
Loop
Wend

Answer 9

I think you are intended to contain ALL YOUR LOGIC under your if statement. Basically:
' PRINTS EVERYTHING EXCEPT 4
For i = 0 To 10
' you want to say
' If i = 4 CONTINUE but VBScript has no continue
If i <> 4 Then ' just invert the logic
WSH.Echo( i )
End If
Next
This can make the code a bit longer, but some people don't like break or continue anyway.