Detect if Solution is offline using TFS and vS 2008 and C#

I have开发者_JS百科 a VS addin in C#.

I want detect if a solution is offline (about TFS) for show warning to user.

I have references like Microsoft.Teamfoundation.Client and others.

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The server's offline state is stored in a registry value named Offline. You should note that the online/offline state of a server is only checked for when the solution is opened.

It is stored under the registry key:

HKEY_CURRENT_USER\Software\Microsoft\VisualStudio\9.0\TeamFoundation\Servers\<tfs server name>\Offline