Microsoft将此规则用作其复杂性规则之一：
Any Unicode character that is categorized as an alphabetic character but is not uppercase or lowercase. This includes Unicode characters from Asian languages.
测试通常的规则,如大写可以像password.Any(char.IsUpper)一样简单.
我可以在C#中使用什么测试来测试非大写或小写的字母Unicode字符？
解决方法
规则的字面翻译怎么样：
password.Any(c => Char.IsLetter(c) &&
!Char.IsUpper(c) &&
!Char.IsLower(c))
