Instead of documenting within the code, many developers choose to use source code management tools, such as GitHub or Visual Studio Team Services.
Tools like these allow you to create change requests and connect changed code to these requests. Once the change is validated, it is connected to the documentation, automatically creating a knowledge database outside of the source code. This keeps the source code clean and readable.
Out-of-the-box Microsoft does not support integration with any source code management tool, but we can find many third-party solutions on the Web. Some tools and additional information can be found at these websites: