Is there a way of intercepting some method calls without making any code changes around the method itself?
I don\'t need to inject any custom behaviour at runtime,
What you are looking for is Fody: https://github.com/fody
Its open source, stable and has lots of plugins for different AOP use cases. I am using it in a huge commercial application, and it is working very well. Installation and configuration is super easy and done within some minutes via nuget.
Some example plugins are:
Requirements, examples and docs can be found on fodys github pages.