是否在类名前加下划线是确保类在库外部不可用的正确方法？

Question

If I have a helper class defined in a library that I don't want utilized outside of the library, is the correct hiding mechanism to place an underscore in front of the class name?

part of foo;

class Bar { } // made available to users of the foo library

class _BarHelp { } // hidden from users of the foo library

Or is there an alternate way of hiding BarHelp ?

Answer 1

是的，下划线适用于与函数，方法和字段相同的类名，这使它们成为库私有的。

Answer 2

Yes. this is correct way and there is no better way to do this in Google Dart language.
It is also the only possible way to use the privacy (does not provided other levels of privacy).