The code below demonstrates std::string usage with Node++ functions and macros.
Both string styles can coexist in harmony even in the same OUT calls.
npp_app.h
#define NPP_CPP_STRINGS
npp_app.cpp
void npp_app_main()
{
OUT_HTML_HEADER;
OUT("<h1>%s</h1>", NPP_APP_NAME);
/* display form */
OUT("<p>Please enter your name:</p>");
OUT("<form action=\"welcome\"><input name=\"name\" autofocus> <input type=\"submit\" value=\"Run\"></form>");
/* try to get the query string value */
QSVAL qs_name_c; // C-style query string value
std::string qs_name_cpp; // C++ string query string value
if ( QS("name", qs_name_c) ) // if present, bid welcome
OUT("<p>Welcome %s, my dear C-style friend!</p>", qs_name_c);
if ( QS("name", qs_name_cpp) ) // read name again into the second variable
OUT("<p>Welcome %s, my dear C++ friend!</p>", qs_name_cpp);
if ( QS("name", NULL) ) // now only check for presence
OUT("<p>Welcome %s and %s, my dear friends!</p>", qs_name_c, qs_name_cpp);
OUT_HTML_FOOTER;
}