how to get solution path

I have a website project, I added a class project and test project on the solution. The structure of my site is like this:
C:\Users\lynda\Documents\Visual Studio 2008\Projects\Working_copy\wwwroot\
test project:
C:\Users\lynda\Documents\Visual Studio 2008\Projects\Working_copy\wwwroot\Testwwwroot
class project
C:\Users\lynda\Documents\Visual Studio 2008\Projects\Working_copy\wwwroot\ClassLibrary
I need to access resource file in C:\Users\lynda\Documents\Visual Studio 2008\Projects\Working_copy\wwwroot\Rescources\ from my test project and class library, How can I get the path:C:\Users\lynda\Documents\Visual Studio 2008\Projects\Working_copy\wwwroot\
Thank you
Best Regards
Li Aishen
 
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