Method is_multipart_form_data

examples/server/httplib.h:4874–4877

}

inline bool Request::is_multipart_form_data() const {
  const auto &content_type = get_header_value("Content-Type");
  return !content_type.rfind("multipart/form-data", 0);
}

inline bool Request::has_file(const std::string &key) const {
  return files.find(key) != files.end();