Two of the three strategies that I explained in my last post Strategies migrating from Visual Studio add-ins to packages involve to avoid the use of the automation model (EnvDTE). When you use an EnvDTE object, basically you do one of three things: to get/set properties, to invoke methods to perform actions and to get events. So, you need to learn how to do that with Visual Studio interfaces of services.

If you follow my third strategy, likely you will define an interface named IHost with some properties like this:

public interface IHost
{
   string RegistryRoot { get; }
   string InstallationFolder { get; }
   …
}

When implementing the RegistryRoot property of that interface using EnvDTE, you would use the DTE.RegistryRoot property. And to implement the InstallationFolder property, you would read the value “ProductDir” of the registry key HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\VisualStudio\<version>\SetupVS.

When implementing those properties of the interface in your package, in this small article I explain how to use the IVsShell interface of the SVsShell service to avoid the use of EnvDTE.DTE to get some information about the Visual Studio IDE (the shell).

HOWTO: Get information about the Visual Studio IDE from a Visual Studio package.
http://www.mztools.com/articles/2014/MZ2014011.aspx