VCFileConfiguration ExcludeFromBuild slow

Hi

I using VCFileConfiguration.ExcludeFromBuild setting to exclude some files from the build, but this doesn't work well for large filesets as it is very slow.

Is there an alternate API that allow to this but faster?

I see that setting this results in a nested element added to the MSbuild underlying project

<ClCompile Include=Foo.cpp"> <ExcludeFromBuild Condition="">true</ExcludeFromBuild></ClCompile Include=Foo.cpp">