Here is a list of some sites that may be of interest to you:
http://www.helixoft.com/blog/archives/28

I especially suggest this URL from the list:
http://www.mztools.com/resources_vsnet_addins.aspx
This is the most complete repository of add-in resources I'm aware of.

You are welcome, Bob.

Tip: You may face an issue that, after some time a Visual Studio .NET
add-in no longer receives events. This is because when the procedure exits
the variable is no longer used and it will be garbage collected.  To
resolve this issue, you must declare the solutionEvents variable at class
level, not at procedure level.

http://support.microsoft.com/kb/555430/en-us
[PRB: Visual Studio .NET events being disconnected from add-in.]

Have a great day. Feel free to let us know if you face any further issue.
We are glad to assist you.

Have a great day,
Best regards,
Wen Yuan

Microsoft Online Community Support
Delighting our customers is our #1 priority. We welcome your comments and
suggestions about how we can improve the support we provide to you. Please
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This posting is provided "AS IS" with no warranties, and confers no rights.

As you will recall, my original question asked about how to extend the IDE for
just one particular solution.  It turns out that VS supports a thing called a
"solution add-in", in which VS stores info in the sln file that instructs the
IDE to load a particular add-in when that solution is opened.  This is
documented here:

http://msdn2.microsoft.com/en-us/library/ms165621(VS.80).aspx

There is just one minor problem... That help topic is misleading, incomplete,
and in some places just plain wrong.  I burned an MSDN tech support case and
worked out how to actually implement a solution add-in with the support
engineer.

I posted this same response over in the microsoft.public.dotnet.languages.vb NG
(since that's where I started a long thread on this subject).  Here, for the
entertainment and edification of anyone who might be interested, is how to wire
up a "solution add-in":

To begin, create a new Add-in project.  Make sure you tell the wizard not to
automatically load your add-in.

Now, in order to work, this add-in must be registered with COM.  This is because
this add-in is going to call the AddIns.Add method, which requires the target of
the method to be an add-in registered with COM.  The "easy" way to register your
assembly with COM is to check the "Register for COM interop" check box on the
Compile tab of the project properties.  However, this requires that you run with
admin privileges, because VS will try to fiddle with the registry every time you
build or clean your project.  We're going to set things up so that we can
manually register the assembly (with admin privileges) but otherwise we can
build and test without admin privileges.

In order to register your assembly with COM (via regasm) you need to strong-name
sign it.  The process to do this is well documented.

You also need to hard-code the assembly version so that the version number
registered with COM agrees with the version number you're actually deploying and
running.

In AssemblyInfo.vb (sorry C# folks, you need to translate this yourselves ;-)
 ' Hard-code the assembly version because
 ' we are going to strong-name sign the assembly
 <Assembly: AssemblyVersion("1.0.0.0")>

 ' Specify a TypeLib GUID to expose this assembly to COM
 <Assembly: GuidAttribute("your TypeLib GUID here")>

In Connect.vb, add the following lines before the class declaration:
 <ClassInterface(ClassInterfaceType.None)> _
 <Guid("your class GUID here")> _
 <ComVisible(True)> _

This magic provides the metadata that regasm uses to expose your class to COM.
(Note that the two GUID values above must be different!)  After you've built
your assembly, you need to run regasm as administrator.  Right-click on the
shortcut to the VS 2005 command prompt and select "Run As..." and run the
command prompt as administrator.  Then type in:

   regasm /codebase <path to your dll>

Now, in the OnConnection routine, we're going to add code that recognizes when
the user selects our add-in in the add-in manager.  When that happens then we're
going to persist the selection in the current solution (.sln file).  Thereafter,
whenever the user opens this solution, our add-in will automatically load and
run.

 Public Sub OnConnection(...) _
 Implements IDTExtensibility2.OnConnection
   _applicationObject = CType(application, DTE2)
   _addInInstance = CType(addInInst, AddIn)

   ' If the user enables this add-in via the Add-In Manager then
   ' add this add-in to the solution's set of "registered" add-ins
   If connectMode = ext_ConnectMode.ext_cm_AfterStartup Then
     With _addInInstance
       _applicationObject.Solution.AddIns.Add(
               .ProgID, .Description, .Name, .Connected)
     End With
   End If
 End Sub

(Note that you probably need to add error handling code.  For example, the user
may select the add-in without first loading a solution.)

Finally, despite what the documentation says, you need to retain the ".AddIn"
files so that your add-in shows up in the Add-In Manager.

Good luck...

Robert Altman