I'm asked this question very frequently, if it's smart to use "Share project..." if a eclipse project has been disconnected from it SVN counterpart in the repository. So, I append my answer to this thread.
The SVN-Team option "Share project ..." is totally fine for projects that exist in SVN and in your Eclipse workspace, even if the Eclipse project is missing the hidden .svn configuration. You can still connect them. Eclipse SVN-implementation (Subclipse/Subversive) will verify if the provided SVN http(s) source is populated. If yes, all existing files will be copied and linked (checked out in SVN terms) to your very personal Eclipse workspace.
Word of caution:
regards, Feder