Bin 建立产品的工作目录，存放项目中所有可执行文件的当前版本；
Lib 与项目有关的库文件；
SQL 存放数据库的SQL文件(只针对数据库程序的开发)；
Res 包括应用程序的所有共享资源，如ICON(图表)、资源文件等；
Pic 图片
Include 公用的窗体或Unit；
Control 存放项目内用的自编或第三方提供的控件；
Source 程序源代码 ；
Public 可以公用的模块或程序；
还是使用Google找了一下，如何给C#中的解决方案，分好文件夹和目录
http://programmers.stackexchange.com/questions/40394/how-do-you-organize-your-projects
Here is the basic solution layout that I always start with. As the projects get better defined I refine it to meet the specific needs of the project. Some areas may be merged with others and I may add a few special ones as needed.
最上层1SolutionName
（1）.ProjectNameDocuments
For large projects there are certain documents that need to be kept with
it. For this I actually create a seperate project or folder within the
solution to hold them.
（2）.ProjectNameUnitTest
Unit testing always depends on the project some times it is just really
basic to catch edge cases and some times it is set up for full code
coverage. Recently have added graphical unit testing to the arsenal.
（3）.ProjectNameInstaller
Some projects have specific installation requirements that need to be
handled at a project level.
（4）.ProjectNameClassLibrary
If there is a need for web services, APIs, DLLs or such.
（5）.ProjectNameScripts (**Added 2/29/2012**)
I am adding this because I just found a need for one in my current project.
This project holds the following types of scripts: SQL (Tables, procs, views),
SQL Data update scripts, VBScripts, etc.
（6）.ProjectName
a.DataRepository
Contains base data classes and database communication. Sometimes
also hold a directory that contains any SQL procs or other specific
code.
b.DataClasses
Contains the base classes, structs, and enums that are used in the
project. These may be related to but not necessarily be connected to
the ones in the data repository.
c.Services
Performs all CRUD actions with the Data, done in a way that the
repository can be changed out with no need to rewrite any higher
level code.
d.Business
Performs any data calculations, business level data validation, does
most interaction with the Service layer.
e.Helpers
I always create a code module that contains helper classes. These
may be extensions on system items, standard validation tools,
regular expressions or custom built items.
f.UserInterface
The user interface is built to display and manipulate the data.
UI Forms always get organized by functional unit namespace with an
additional folder for shard forms and one for custom controls.
项目与项目之间的dll引用问题
A项目生成dll，B项目引用A项目生成的dll
如果通过浏览的方式去引用dll，加入更换了A项目的生成路径，那么B项目引用的仍然是原来的dll
如果通过添加引用-->项目来引用的话，A项目的路径变化的话，B项目引用的dll路径会自适应