将int附加到std :: string

Question

为什么此代码给出调试断言失败？

   std::string query;

   int ClientID = 666;

   query = "select logged from login where id = ";

   query.append((char *)ClientID);

Answer 1

您不能将int强制转换为char *以获取字符串。尝试这个：std::ostringstream sstream;sstream << "select logged from login where id = " << ClientID;std::string query = sstream.str();