I try to follow the instructions at regex visual studio by adding the following line to the header file:

#include <iostream>
#include <regex>

And add the following line to the .cpp file:

using namespace std;

void CTestMemcmpDlg::OnBnClickedButton3()
{
    // TODO: Add your control notification handler code here
    std::regex rex1(R"((.+?)([^\.]+.[^\.]+)$)");
    std::smatch m;
    std::string str = "c:\Python27\REGEX\test_regex.py";
    if (regex_search(str, m, rex1)) {
        std::cout << "Path: " << m[1] << std::endl;
        std::cout << "File name: " << m[2] << std::endl;
    }
}

But always get the compiler error:

error C2039: 'regex' : is not a member of 'std'

Why?