正则表达式 C++：提取标签之间的子字符串

Question

I would like to extract a some substring between two tags. Example: <column r="1"><tb="red"><v>1</v></t></column> I would like to get: <tb="red"><v>1</v></t>

I don't want to use boost or other libs. Just standard stuffs from C++, except CERN's ROOT lib, with TRegexp, but I don't know how to use it...

Answer 1

You shouldn't be using regexes to try to match html, but, for this special case, you could do:

#include <string>
#include <regex>

// Your string
std::string str = "<column r="1"><t b=\"red\"><v>1</v></t></column>";

// Your regex, in this specific scenario
// Will NOT work for nested <column> tags!
std::regex rgx("<column.*?>(.*?)</column>");
std::smatch match;

// Try to match it
if(std::regex_search(str.begin(), str.end(), match, rgx)) {
  // You can use `match' here to get your substring
};

As Anton said above: don't .