Situation
I run a build system that executes many builds for many project. To avoid one build impacting another we lock down the build user to only its
For my original answer to a similar question see: TFS Build server and COM references - does this work?
A good way to compile .NET code that references COM components without the COM components being registered on the build server is to use the COMFileReference
reference item in your project/build files instead of COMReference
. A COMFileReference
item looks like this:
<ItemGroup>
<COMFileReference Include="MyComLibrary.dll">
<EmbedInteropTypes>True</EmbedInteropTypes>
</COMFileReference>
</ItemGroup>
Since Visual Studio provides no designer support for COMFileReference
, you must edit the project/build file by hand.
During a build, MSBuild extracts the type library information from the COM DLL and creates an interop assembly that can be either standalone or embedded in the calling .NET assembly.
Each COMFileReference
item can also have a WrapperTool
attribute but the default seemed to work for me just fine. The EmbedInteropTypes
attribute is not documented as being applicable to COMFileReference
, but it seems to work as intended.
See https://docs.microsoft.com/en-ca/visualstudio/msbuild/common-msbuild-project-items#comfilereference for a little more detail. This MSBuild item has been available since .NET 3.5.
It's a shame that no-one seems to know anything about this technique, which to me seems simpler than the alternatives. It's actually not surprising since I could only find just the one above reference to it on-line. I myself discovered this technique by digging into MSBuild's Microsoft.Common.targets file.
in .NET COM is normally done thru Interop in order to register .DLL in .NET they are called Assemblies and that can be done several ways.. by adding references via VS IDE at the project level, or writing code that Loads and unloads the assembly.. by .Config file that haas the reference to the assembly as well as the using of that reference within the project... GAC.
There's a walkthrough on registration-free COM here:
http://msdn.microsoft.com/en-us/library/ms973913.aspx
And excruciating detail here: http://msdn.microsoft.com/en-us/library/aa376414 (the root of that document is actually here: http://msdn.microsoft.com/en-us/library/dd408052 )
Also, for building in general, you should be able to use Tlbimp or tlbexp to create a TLB file that you can use for building, assuming the point of registering is just to be able to compile successfully, and not to run specific tests.
Thanks for all the help.
We changed from early-binding to late-binding because we never really needed the DLL at compile time. This pushed the registration requirement from the build server to the integration test server (where we execute the installer which handles the registration). We try to keep the build system pristine and have easy-to-reset integration systems.
Thanks again Peter
Installation tools such as Installshield can extract the COM interfaces from the DLLs and add them to the registry. It can also use the self-registration process of the DLL (which I believe is what regsvr does), but this is not a Microsoft installer best practice.