節錄如下 1. Close all apps (not really needed, but simplifies things) 2. Open game center and create a sandbox account (no need to verify email address) 3. Log out of this new account by tapping your email address under the 3 boxes. 4. Close game center and then make sure it’s removed from the multi-tasking bar 5. Open a game center enabled game and be presented with the normal game center login!