Richard,
As far as I could see if I 'play nasty with it and pass direct interface
pointers to other threads', interop does the marshalling automatically [by
direct interface pointers I mean here C# wrapper reference]. Do you know of
a way to get to the real interface pointer and create the wrapper
explicitly?
Concerning thread safety - I am quite sure it is thread safe, lived for a
while with that component.
Unfortunately setting 'Both' at registry does not make VS happy, it still
does the marshalling.
What I need, is, actually, to run ActiveX method that may block (but doesn't
deal with UI) in a safe way when it comes to server application, so each
call to ActiveX method must be made on separate thread.
You may ask why ActiveX , if no UI ? -- well that's because of 'historical
reasons':)
With best regards,
Pavlo Batsii
----- Original Message -----
From: "Richard Blewett" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Tuesday, September 11, 2007 4:13 PM
Subject: Re: [ADVANCED-DOTNET] MTA ActiveX - .NET interop
The problem is that an activeX control has to run in an STA and therefore
all calls to it will be marshalled on to a single thread (unless you play
nasty with it and pass direct interface pointers to other threads).
ActiveX controls are not usually written with multithreading in mind - how
do you know its threadsafe? If it truely is thread safe and ok to call
from
an MTA thread you could try setting your threading model to Both and see
if
VS will be happy with that (I've not tested that).
Regards
Richard Blewett - DevelopMentor
-----Original Message-----
From: Discussion of advanced .NET topics. [mailto:ADVANCED-
[EMAIL PROTECTED] On Behalf Of Pavlo Batsii
Sent: 11 September 2007 13:56
To: [email protected]
Subject: Re: [ADVANCED-DOTNET] MTA ActiveX - .NET interop
Richard,
I have inherited the component and it has some legacy UI which must be
kept
(for other native clients).
The context in which I would like to run ActiveX code doesn't involve
its
UI.
I would rather avoid splitting the component, also I would avoid
converting
it to clean COM component, if that's possible.
Thanks &
with best regards,
Pavlo Batsii
----- Original Message -----
From: "Richard Blewett" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Tuesday, September 11, 2007 3:33 PM
Subject: Re: [ADVANCED-DOTNET] MTA ActiveX - .NET interop
>I have a couple of questions.
>
> Is the control a UI element or is it just a component you want to use
for
> automation purposes that doesn;t have a UI (say like a timer)?
> Have you authored the control or is it a component developed
elsewhere?
>
> Regards
>
> Richard Blewett - DevelopMentor
>
>> -----Original Message-----
>> From: Discussion of advanced .NET topics. [mailto:ADVANCED-
>> [EMAIL PROTECTED] On Behalf Of Pavlo Batsii
>> Sent: 11 September 2007 10:53
>> To: [email protected]
>> Subject: [ADVANCED-DOTNET] MTA ActiveX - .NET interop
>>
>> How do can man use ActiveX controls from .NET WinForms app
>> so that reference to the IDispatch-implementing object retrieved
from
>> ActiveX control wrapper wouldn't be necessarily marshalled to the
main
>> thread and ActiveX code not invoked from STA thread's context? A
kind
>> of , I would presume, a trivial question that is, only that I
couldn't
>> get an answer anywhere.
>>
>> I'll explain:
>>
>> if one adds the ActiveX on a form, retrieves a pointer to some
>> automation object, and tries to call that pointer from other
thread's
>> context (not from main form, for example), .NET interop marshalls
the
>> pointer to the main form (by putting a windows message to the form's
>> message queue and processing call at the main form, (in a
>> BackgroundWorker fashion?)), so that all calls to ActiveX methods
are
>> made from the same thread.
>>
>> I would like to avoid this, because ActiveX component is thread-safe
>> and, actually, such behaviour is not acceptable since ActiveX method
>> may block, and it is invoked from a server application (that is,
>> ActiveX method implementation must be called asynchronously, not one
by
>> one).
>>
>> If ActiveX is registered as MTA @ registry then VS designer throws
an
>> exception when dragging ActiveX on a form.
>>
>> Any solutions in case this marshalling cannot be 'disabled'?
>>
>> Thanks!
>>
>>
>>
>>
>>
>> If I add ActiveX control on a form (WinForm application),
>> get a reference to some
>>
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