c++ - std::string 到 int8_t

Question

这给出了一个 bad_lexical_cast 异常:

int8_t i = boost::lexical_cast<int8_t>("12");

当值不适合 int8_t 时，我想有一个异常(exception)。

我应该怎么做？如果值超出 -128 到 127 的范围，我应该先转换为 int 并抛出异常吗？

我也对将字符串转换为 uint8_t 感兴趣。

Answer 1

Q: What does lexical_cast of an int8_t or uint8_t not do what I expect?

A: As above, note that int8_t and uint8_t are actually chars and are formatted as such. To avoid this, cast to an integer type first

来源:

http://www.boost.org/doc/libs/1_51_0/doc/html/boost_lexical_cast/frequently_asked_questions.html