不，官方SDK中没有办法做到这一点，你不能在后台使用它，因为它不属于后台运行类别，除非您的应用在后台执行其他操作，然后只是监控呼叫.

No there is no way to do this in the official SDK, you can not use it in the background since it does not fall on of the background running categories unless you app does something else in the background then just monitoring the call.

您将永远无法获得当前通话的电话号码，因为这是私人数据，Apple 不允许您访问这些数据.

You will never be able to get the phone number of the current call since this is private data Apple will not allow you to acces the data.