Using Inner classes in C#

Question

What are the best practices regarding the use and structure of inner classes in C#.

For instance if I have a very large base class and two large inner classes should

Answer 1

I personally use inner classes to encapsulate some of concepts and operations used only internally within a class. This way I don't pollute that class' non-public api and keep the api clean and compact.

You can take advantage of partial classes to move the definition of these inner classes into a different file for better orgnanization. VS does not automatically group partial class files for you except for some of the templatized items such as ASP.NET, WinForm forms, etc. You will need to edit the project file and make some changes in there. You can look at one of the existing grouping in there to see how it is done. I believe there are some macros that allow you to group partial class files for you in the solution explorer.