Is there a SelectionSet usage limit?

This is weird, but has anyone heard of or come across a limit on the number
of times a selectionset can be re-used? I've got a monster app written in
VB.NET using COM INTEROP that creates wiring schematics based on
information retrieved from a C# webmethod - it automates the drawing task
in AutoCAD 2005.

The program pops an error every time on the 37th pass. I've checked all the
obvious things I can think of - yes, the blocks are valid, are actually
inserted and haven't been erased as is reported in the error. I've also
reordered my JOB so the 37th pass contains different blocks just to make
sure. At this moment in the program, about 350-600 blocks have been insert
into the sset [2 to 60 per loop] during the 36 previous passes and the sset
is deleted before it starts the next loop. I've even tried clearing the
sset instead of deleting it. Since the program is massive, here's just the
portion in question:

For lCntr = 1 To Job.Count
'grab Component from JOB
oComponent = Job.Item(lCntr)
'create an AutoCAD Selection Set
cadSSet = m_cadDoc.SelectionSets.Add("iDrawing")
'insert graphic and set reference to blockref
cadBRef = InsertComponent(oComponent)
'add blockref to selectionset
cadBRefs(0) = cadBRef
cadSSet.AddItems(cadBRefs)
'loop to insert all subcomponents
For lCntr2 = 1 To oComponent.Item.Count
'insert graphic and set reference to blockref
cadBRef = InsertComponent(oComponent.Item(lCntr2))
'add blockref to selectionset
cadBRefs(0) = cadBRef
cadSSet.AddItems(cadBRefs)
Next

'move into position, populate attributes, etc.
'PASSING SelSet BYREF so it records update insertion points
'ERROR OCCURS HERE - iNVALID POINTER: OBJECT(S) ERASED
ProcessComponentCluster(cadSSet)
'clear vars for next pass
cadSSet.Delete()
oComponent = New Component
cadBRef = Nothing
Next

My next step is to try concantenating the counter value [lCntr] to the sset
name and see if that resolves it. I thought I'd post this so anyone who
might have run into can hopefully answer before I come back if this idea
fails - can you tell I have a tight deadline

Thanks,

-- Mike
___________________________
Mike Tuersley
CADalyst's CAD Clinic
Rand IMAGINiT Technologies
___________________________
the trick is to realize that there is no spoon...

 

Odd.

Have you breakpointed prior to the subr call to verify each object in the
selection set? Object erased sounds like the type of error when an
AcadEntity is deleted. Without the oComponent class or the InsertComponent
procedure it is a bit tough. My bet is that:

cadSSet.AddItems(cadBRefs)

is somehow passing a bad object.


(Don't you just hate deadlines?)

--
R. Robert Bell


This is weird, but has anyone heard of or come across a limit on the number
of times a selectionset can be re-used? I've got a monster app written in
VB.NET using COM INTEROP that creates wiring schematics based on
information retrieved from a C# webmethod - it automates the drawing task
in AutoCAD 2005.

The program pops an error every time on the 37th pass. I've checked all the
obvious things I can think of - yes, the blocks are valid, are actually
inserted and haven't been erased as is reported in the error. I've also
reordered my JOB so the 37th pass contains different blocks just to make
sure. At this moment in the program, about 350-600 blocks have been insert
into the sset [2 to 60 per loop] during the 36 previous passes and the sset
is deleted before it starts the next loop. I've even tried clearing the
sset instead of deleting it. Since the program is massive, here's just the
portion in question:

For lCntr = 1 To Job.Count
'grab Component from JOB
oComponent = Job.Item(lCntr)
'create an AutoCAD Selection Set
cadSSet = m_cadDoc.SelectionSets.Add("iDrawing")
'insert graphic and set reference to blockref
cadBRef = InsertComponent(oComponent)
'add blockref to selectionset
cadBRefs(0) = cadBRef
cadSSet.AddItems(cadBRefs)
'loop to insert all subcomponents
For lCntr2 = 1 To oComponent.Item.Count
'insert graphic and set reference to blockref
cadBRef = InsertComponent(oComponent.Item(lCntr2))
'add blockref to selectionset
cadBRefs(0) = cadBRef
cadSSet.AddItems(cadBRefs)
Next

'move into position, populate attributes, etc.
'PASSING SelSet BYREF so it records update insertion points
'ERROR OCCURS HERE - iNVALID POINTER: OBJECT(S) ERASED
ProcessComponentCluster(cadSSet)
'clear vars for next pass
cadSSet.Delete()
oComponent = New Component
cadBRef = Nothing
Next

My next step is to try concantenating the counter value [lCntr] to the sset
name and see if that resolves it. I thought I'd post this so anyone who
might have run into can hopefully answer before I come back if this idea
fails - can you tell I have a tight deadline

Thanks,

-- Mike
___________________________
Mike Tuersley
CADalyst's CAD Clinic
Rand IMAGINiT Technologies
___________________________
the trick is to realize that there is no spoon...

 

Yeah, I know that would be my reply =)

Nope, each blockref passed to the cadBref array is valid as is the array
itself.

And I thought the C# webmethods intergrated was going to be the hard part -
NOT AutoCAD!

no reply - this is a monitored group

--
-- Mike
___________________________
Mike Tuersley
CADalyst's CAD Clinic
Rand IMAGINiT Technologies
___________________________
the trick is to realize that there is no spoon...

 

Well, poo. (moderator or no!)

I notice that there is no:
cadSSet = Nothing

I'm phishing now, with you, but could that help you?

--
R. Robert Bell

Yeah, I know that would be my reply =)

Nope, each blockref passed to the cadBref array is valid as is the array
itself.

And I thought the C# webmethods intergrated was going to be the hard part -
NOT AutoCAD!

no reply - this is a monitored group

--
-- Mike
___________________________
Mike Tuersley
CADalyst's CAD Clinic
Rand IMAGINiT Technologies
___________________________
the trick is to realize that there is no spoon...

 

I notice that there is no:

I'm glad your phishing with me, Robert. I just sent youi an email. I don't
know - will try it. While it should be there, I would've thought it'd stick
it's ugly little head up before the 37th time thru?????

Man, I never have simple problems

Thanks a million Robert =)

 

Hey, we're making headway! Adding the nothing increased my error to
catastrophic - now that is messed up!!!

"An unhandled exception of type
'System.Runtime.InteropServices.COMException' occurred in
SchematicGenerator.exe

Additional information: Catastrophic failure"

[gonna be a looonnnnggggggg night]

-- Mike
___________________________
Mike Tuersley
CADalyst's CAD Clinic
Rand IMAGINiT Technologies
___________________________
the trick is to realize that there is no spoon...

 

Why this rather than reusing the same set each time?

I noticed Robert's comment about cadBRef = Nothing.

While I don't know if it's related to your problem this bit of code doesn't
do what you might think. If you're handling a COM object, you need to
explicitly release the reference with Marshal.ReleaseComObject as setting
the reference to Nothing does not decrement the reference count. I've had
that problem bite me more than once in COM interop projects. Police your COM
references zealously.

Also, where's the code for ProcessComponentCluster()?

 

Have a look at my notes on the use of Nothing with respect to COM objects.

 

Thank you Frank!

duh! I missed that one. It *should* be before the loop

Hmm never thought of that one - all of my cad objects are set to nothing
come to think of it :-[

I know, I know, I need smacked for not posting but its more complicated
than I posted. ProcessComponentCluster is actually a function that branches
out to 4 or 5 others, but it is the only one that does anythng to the
selset. The drawing is organized into "columns" then cut into sheets via
layouts. PCC calls functions that
1. determine the overall bounding box of the selset
2. determine the next column that has the vertical space free to place the
selset in
3. If no column exists with enough vertical space, a sub is called tto
create another
4. The selset is moved into position - the only time the selset is actually
edited. It returns back fine -> X objects get sent, X objects return

I'm gonna try your suggestions here and ten post ALL the processing code if
it doesn't work! Thanks again Frank and Robert - you guys shave no idea how
much I appreciate it.

-- Mike
___________________________
Mike Tuersley
CADalyst's CAD Clinic
Rand IMAGINiT Technologies
___________________________
the trick is to realize that there is no spoon...

 

Frank, what is a valid check to use on a com object prior to
Marshal.ReleaseComObject? Should I use a If Not object = Nothing approach,
or something different/better?

-- Mike
___________________________
Mike Tuersley
CADalyst's CAD Clinic
Rand IMAGINiT Technologies
___________________________
the trick is to realize that there is no spoon...

 

In C#, I always use this:

if (obj != null) {
Marshal.ReleaseComObject(obj);
obj = null;
}

Your code looks the same thing in VB but it's been a while so I'm not sure.

 

Thanks! If it wasn't for the client requiring vb.net, I would rather have
done c# - as we've discussed, I've made too many of my own problems because
I automatically think in vb6 terms.

-- Mike
___________________________
Mike Tuersley
CADalyst's CAD Clinic
Rand IMAGINiT Technologies
___________________________
the trick is to realize that there is no spoon...

 

This is directly from the Acad help file.

so AutoLISP is not permitted to have more than 128 open at one time. If this
limit is reached, AutoCAD refuses to create any more selection sets and
returns nil to all ssget calls. To close an unnecessary selection set
variable, set it to nil.

HTH
Matthew