字符串中的TRIM操作
std::string& ltrim(std::string& str, const std::string& chars = "\t\n\v\f\r "); std::string& rtrim(std::string& str, const std::string& chars = "\t\n\v\f\r "); std::string& trim(std::string& str, const std::string& chars = "\t\n\v\f\r ");
std::string& ltrim(std::string& str, const std::string& chars) { str.erase(0, str.find_first_not_of(chars)); return str; } std::string& rtrim(std::string& str, const std::string& chars) { str.erase(str.find_last_not_of(chars) + 1); return str; } std::string& trim(std::string& str, const std::string& chars) { return ltrim(rtrim(str, chars), chars); }