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工程中,需要从字符串中匹配出以:开头,并以:结束的字符串。 Google还是百度,很多C++的正则表达式都是通过st::tr1或boost库中使用的,但是我们仅仅用一个小小的功能,就用一个库不是很好的办法。 对的,之前我的博客已经介绍了C++11的新特性-正则表达式。 所以可以不使用其他的库,来完成任务: ~~~ std::vector<string> all_sub_string = {}; std::string all_string = "12:wo:sfd:wom::sdf"; std::regex e(":[a-z0-9_+-]+:");//正则规则 const std::sregex_token_iterator end; for (std::sregex_token_iterator i(all_string .begin(), all_string .end(), e); i != end; ++i) { all_sub_string .push_back(*i); } ~~~ 你可能会迷惑,什么是sregex_token_iterator? 不要着急,sregex_token_iterator其实就是字符串 regex_token_iterator 的类型定义。 ~~~ typedef regex_token_iterator<string::const_iterator> sregex_token_iterator; ~~~ 上面的方法很简单,就像使用迭代器一样。 其实regex还有其他的查找方法,现在介绍一下regex_search: Returns whether some sub-sequence in the target sequence (the subject) matches the regular expression rgx (the pattern). The target sequence is either s or the character sequence between first and last, depending on the version used. 直接上代码: ~~~ // regex_search example #include <iostream> #include <string> #include <regex> int main () { std::string s ("this subject has a submarine as a subsequence"); std::smatch m; std::regex e ("\\b(sub)([^ ]*)"); // matches words beginning by "sub" std::cout << "Target sequence: " << s << std::endl; std::cout << "Regular expression: /\\b(sub)([^ ]*)/" << std::endl; std::cout << "The following matches and submatches were found:" << std::endl; while (std::regex_search (s,m,e)) { for (auto x:m) std::cout << x << " "; std::cout << std::endl; s = m.suffix().str(); } return 0; } ~~~ 输出: ~~~ Target sequence: this subject has a submarine as subsequence Regular expression: /\b(sub)([^ ]*)/ The following matches and submatches were found: subject sub ject submarine sub marine subsequence sub sequence ~~~