public static TwitterAccount BacktrackFallback(TwitterAccount account) { if (!Setting.IsBacktrackFallback.Value) { return account; } var cinfo = account; while (true) { var backtrack = Setting.Accounts.Collection.FirstOrDefault(a => a.FallbackAccountId == cinfo.Id); if (backtrack == null) return cinfo; if (backtrack.Id == account.Id) return account; cinfo = backtrack; } }