I'm writing a Visual Studio add-in using C/C++. I am not familiar with the COM architecture. In fact I'm learning Windows programming.
I can see an OnDisconnect() call back into my add-in. I tried returning S_FALSE, but that does not seem to stop the add-in from being unloaded.
So my questions is, is it possible to make an add-in that cannot be unloaded (either through the Tools menu or programatically), and if yes, will some magic return value from OnDisconnect() do the job, or some other trick is required?
I also saw another question that asks exactly the opposite. From the answer, it seems that the DLL still resides in the memory when an add-in is unloaded. So maybe there is a way to reload the add-in as soon as it is unloaded?
I don't know of any way to do this. If you really need functionalty that cannot be unloaded while VS is running, you should write a package instead of an add-in.
Related
I have a solution with several projects that have Register for COM Interop checked.
I have a Visual Basic 6 project that references the resulting TLBs. One issue with VB6 is when it references a dll/tlb, it puts a lock on that file.
Using Visual Studio 2010, unless I'm doing a rebuild or have made a change to one of these interop projects, I can build/run the solution (with the VB6 project open) without it barking that one or more of the assemblies is locked.
However, using Visual Studio 2012, even on a simple build where nothing has changed, apparently it always does the regasm, which makes it impossible for me to debug my VB6 project.
Is this new feature of Visual Studio of running regasm on build something that I can turn off?
EDIT: Allow me to simplify:
Using Visual Studio 2010, I hit Build-->Build Solution and check the output for one of my assemblies that is marked as Register for COM Interop and the file has not changed.
Using Visual Studio 2012, I do Build-->Build Solution and check the same assembly, it has been updated, and does so every time I hit Build Solution.
I want the behavior in Visual Studio 2012 to work the same as it did in 2010.
EDIT (again):
I posted this to Microsoft Connect. If someone answers it there or posts a workaround, I'll urge them to also post the answer here.
I've always encountered problems like this when running VB6 and VS20XX, but I always did a rebuild. My suggestion is to stop using VB6 for testing purposes. I found it was far easier to simply create a testing project and do all of my testing in .NET on my .NET code. This should only require a small amount of set up, but it is well worth it in my opinion.
I know this isn't an answer to your specific question, but it offers an alternative. As far as the problem you are describing, I can't duplicate a change in behavior. I start off with only VS201X open, full solution rebuild, open VB6 and add a reference to an exposed COM DLL. I didn't notice anything unexpected.
Build works fine as long as I haven't changed anything in the COM DLL
Build fails if I changed the COM DLL's code as the file is locked
Rebuild fails as the file is locked
Few question about VSTO project I don't understand:
Registration - unlike native Office Plugin, where I've an installation project, how does the deployment work in managed add-in? After building the project, I do have the necessary entries in the registry that define the plugin (HKCU\Software\Microsoft\Office\Outlook\Addins...). Where is the code that perform this registration?
Also, why in the HKCU? I'd like the plugin to be defined for all users (in HKLM). How do I change that?
How does Visual Studio know to start Outlook, when I press F5? In the property page for the project, under the debugging tab, the 'Start Option' is set to 'Start project'. Who tells Visual Studio that starting the project means starting Outlook?
Looking for more materials about VSTO. Can you recommend a resource?
A few answers
1. Basically the same for a managed project except that the Reg entries point to the .MANIFEST file, which in turn identifies the dll of the addin assembly.
Ohhh. this is a LONG story, there's lots of info on the web about it. Google "registering an addin for all users".
Short version is that it's possible, but requires some really weird and difficult to explain registry shinanigans.
If you've created an Outlook addin property, then by virtue of that project type, VS knows what to do on start.
I've never found a good definitive source for vsto material. Google's been my best friend for that kind of info. Andrew Coates has a pretty decent list here though
http://blogs.msdn.com/b/acoat/archive/2007/08/02/vsto-resources.aspx
I have no explicit information but currently I'm working through http://msdn.microsoft.com/en-us/library/ff937654.aspx which so far has been a great source of information. Please let me know if this worked out for your Outlook project.
Using VB6, I have created an Outlook plugin, that has a property page. The property page is an OCX control.
When I compile the project to an OCX file, and then run OUTLOOK, things work fine: I am able to see my OCX as a tab in the Outlook options.
However, when I try to debug by running the OCX in VB6 I get an error. My debugging is started like this:
1) Debug options set to Wait for components to be created"
2) F5-RUN project in VB6.
3) Start Outlook.
4) Get the error: "Cannot display "MyOcx" page. This page will remain visible, but is not available. An OLE registration error occurred. The program is not correctly installed. Run Setup again for the program"
I suspect this is because, when debugging, the OCX is being created out-of-proc and Outlook doesn't like that.
Is there a good technique to use the VB6 debugger on the OCX in this scenario?
The VB6 debugger is sometimes flaky when debugging DLLs or OCXs.
You could try Windbg, a free standalone debugger from Microsoft. Compile your VB6 OCX into native code with no optimisation and "create symbolic debug info" (i.e. create PDB files), and you will be able to debug your OCX in-process in Outlook. Here's a 2006 blog post by a Microsoft guy about using Windbg with VB6, and 2004 blog post by another Microsoft guy with a brief introduction to Windbg.
You could also use the Visual Studio 2008 debugger with VB6 and PDB files, e.g. with Visual C++ Express Edition (which is free). EDIT see Kris's answer for more details.
EDIT: Both Windbg and Visual Studio expect the source code to be in exactly the same path on the debug machine as it was on the build machine when the OCX was built. The easiest way is to build and debug on the same machine. Otherwise you might need to fiddle with SUBST to create virtual drives - or I'm told the serious way is to use a Symbol Server.
(Les serious) you could do without those newfangled interactive debuggers, just log to a file, or with DebugMessage calls from your VB6.
The only way you are really going to be able to Debug this is In Process as MarkJ said. Using the free Visual Studio 2008 C++ Express Edition (or even better, Visual Studio 2008 Professional if you have it, and it is available for a 90 day trial) and a PDB.
To make sure you are creating the PDB, go into Visual Basic, check the P)roject / P)roperties and click on the Compile tag. Make sure "Create Symbolic Debug Info" is checked.
Next start up Outlook, and attach to that process from Visual Studio (T)ools / Attach To Process. Make sure your Ocx is shown in the modules window, and then load the PDB (right click on the Ocx in the modules window). You will probably have to add the source code in the Solution Properties (for more details on how to do that, read this post).
It's a bit of a pain in the butt the first time, but once you can do it, it becomes pretty easy, and is far easier than trying to determine what is going on from a log.
I don't have much idea on the OCX.
However, you can use a tool which was part of visual studio named something like "activex control test tool".
As far as I know (based on my understanding of documentation), OCX is created in-proc.
I have a legacy VB6 app that I still need to support. I also have a new PC and I would like to copy my custom toolbar that I created on my old PC. Does anybody know where Visual Studio 6 custom toolbars are persisted to?
Thanks
I think you are talking about an addin. Addins written in VB6 for VB6 use a reference to Microsoft Visual Basic 6.0 Extensibility. You compile the application as an ActiveX EXE and as such it can be placed anywhere on the hard drive. You can look at vbaddin.ini for the *addin.*Connect setting where addin will be the addin name. Unfortunately this is not the file name or path, but it should be close enough to help you search the the application.
I don't know where that is stored, but you could try running Process Monitor from SysInternals, and see what VB6 writes to files and the registry when you change your custom toolbar. To be honest though, it'll probably be quicker to set the toolbar up by hand.
I would like to control options on the debugger without using the debugging GUI's, preferably from inside the code being debugged. I would think that would be quite difficult, but maybe my debugged code can request a service from independent code that will communicate with the debugger.
This relates to another question of mine on controlling when to break on exceptions.
You can write Visual Studio macros that can do anything the GUI can, but they can get rather involved. See the MSDN documentation on Automation and Extensibility for Visual Studio
Doing this from the code being debugged would be tricky, you would definitely need some new form of communication with VS, maybe a custom add-in. I don't think an independent service would fundamentally help here. The biggest problem is that your code will stop running when the debugger breaks.
I know that you can do it with WinDBG and OutputDebugString, but for Visual Studio, I think you have to spool off another process, pipe commands to that, and have that manipulate the Debugger API.