This question already has an answer here:
I recently installed Visual Studio 2017 Community and noticed that there is no CodeLens. I had CodeLens enabled on Visual Studio 2015 Community so I'm hoping that its also available for VS 2017 Community. How can I do so? Or is it no longer available for VS 2017 Community edition?
Enabling CodeLens on Visual Studio 2015 Community
You can see the officially enabled set of features per Visual Studio edition on the Compare Offerings page of the Visual Studio website.
A note on CodeLens + SSDT in particular: CodeLens was not officially supported as part of Visual Studio 2015 Community, nor is it supported in Visual Studio 2017. While some earlier versions of the SSDT installer for Visual Studio 2015 may have enabled the feature this was an error fixed in later updates. The official policy is that CodeLens is available in Visual Studio Professional and higher editions.
Codelens in Visual Studio 2015 Community is enabled by installing SSDT 2015 with SSIS & SSAS, but they haven't releases SSDT, SSIS or SSAS 2017. so we have to wait till MS release, after then we could find out....
来源：https://stackoverflow.com/questions/42991430/how-to-enable-codelens-for-visual-studio-2017-community