why we are adding solution folder, and responsibilities share ,test folders inside solution

Question

I have couple of the those pic I loaded.First my question about first pic.why those folders seems with dot presented.when I look ad those folsers,it says they are "solution folders".why we need this folder ,for example I am creating a class libabrary as a project.why should I decribe this project inside the "solution folders".

first pic.

second pic

my second question about this solution struture.which created by Layered Architecture Solution Guidance 2010 download from here http://visualstudiogallery.msdn.microsoft.com/c8c473b5-21a1-447a-8b24-33b43411ee7f

It's already had bll,dal,bo, folder,why we need a share folder.which classes should we put inside it and I also see a test folder.whats primary responsibilityies on this solution.and how it is used. thank you all.

Answer 1

First Question: Those are solution folders, which are just a way of logically separating the different parts of the solution (layers, etc.). You can only have physical folders inside a project (the ones that aren't dotted-lined): Visual Studio Solutions Folder as real Folders

Second: A shared folder could be used for classes that don't neatly fit inside either the BLL or the DAL. I can't think of a reason off the top of my head for one, but I've seen examples where shared classes are created in RIA services for Silverlight.

Bonus: The tests folder is for holding your Unit Tests. Look up Unit Testing for ideas. It is very useful to write Unit Tests for your code to provide a first line of bug-fighting whenever you create (do my tests run successfully on my new code?) or modify (do my tests still run successfully on my existing code after this change I just made). NUnit is a popular open-source Unit Test framework, and MS provides its own Test Project Unit Test framework built into Visual Studio.