C++正则匹配实现提取两个指定字符串之间的字符串

比如Known=4325,guid=qwer233,Element=fdger2354, 把guid=后面的qwer233给提取出来。

即提取“guid=”和“,”之间的字符串。

#include <iostream>
#include <string>
#include <regex>
using namespace std;
 
int main()
{
    string text = "Known=4325,guid=qwer233,Element=fdger2354,";
    cout << text << endl;
    regex pattern(".*?guid=(.*?),.*?");
    smatch results;
    if (regex_match(text, results, pattern)) 
        for (auto it = results.begin(); it != results.end(); ++it)
           cout << *it << endl;
    else 
        cout << "match failed: " << text << endl;
    system("pause");
}      

输出：

#include <iostream>
#include <string>
#include <regex>
using namespace std;
 
string midstr(string oldstr, string startstr, string endstr)
{
  string re = ".*?" + startstr + "(.*?)" + endstr + ".*?";
  regex pattern(re);
  smatch results;
  if (regex_match(oldstr, results, pattern))
    return results[1];
  else
    cout << "match failed: " << oldstr << endl;
 
}
 
 
int main()
{
  string text = "Known=4325,guid=qwer233,Element=fdger2354,";
  string data;
  data = midstr(text, "guid=", ",");
  cout << data << endl;
  system("pause");
}