自动投射几乎总是邪恶的。如果有一个转换 const char * ，一个 std :: string 也可以自动转换为其他指针类型并可能导致很难找到错误。有 c_str（）方法返回 const char * ，所以你仍然可以实现你需要的。此外，类型转换在逻辑上是不正确的 - std :: string 不等同于 const char * 。

Automatic casts are almost always evil. If there were a cast to const char *, a std::string could be also automatically cast to other pointer types and that could lead to hard to find bugs. There is the c_str() method that returns const char * so you can still achieve what you need. Also, the typecast is not logically correct - std::string is not equivalent to const char *.