参见 Wojciech N. 的回答寻求更简单的解决方案！

See Wojciech N.'s answer for a simpler solution!

与NSLocale Swift 3类似，您必须转换覆盖类型Locale 回到它的基础对应 NSLocale 以检索国家/地区代码:

Similarly as in NSLocale Swift 3, you have to cast the overlay type Locale back to its Foundation counterpart NSLocale in order to retrieve the country code:

if let countryCode = (Locale.current as NSLocale).object(forKey: .countryCode) as? String {
    print(countryCode)
}