Question

遵循MySQL C ++连接器上的MySQL站点的语法，但没有取得好的结果，这里有一个片段：

#include "/usr/include/mysql++/mysql++.h"
#include "/usr/include/mysql/mysql.h"
#include "/usr/include/mysql/mysql_version.h"
#include "/usr/include/mysql_connection.h"
#include "/usr/include/mysql_driver.h"
#include <cppconn/driver.h>
#include <cppconn/connection.h>
#include <cppconn/exception.h>
#include <cppconn/resultset.h>
#include <cppconn/statement.h>
#include <cppconn/prepared_statement.h>


using namespace std;
using namespace sql::mysql;
using namespace sql;


sql::mysql::MySQL_Driver *driver;
driver = sql::mysql::get_mysql_driver_instance();
sql::Connection *con;
con = driver->connect("tcp://127.0.0.1:3306", "db", "password");
sql::PreparedStatement  *prep_stmt;
prep_stmt = con->prepareStatement("INSERT INTO db(srcIP, srcCountry, destIP, destHost, destPort, blIP) VALUES (?, ?, ?, ?, ?, ?)");

    prep_stmt->setString(1, src_ip);
    prep_stmt->setString(2, country_code);
    prep_stmt->setString(3, dest_ip);
    prep_stmt->setString(4, host_name);
    prep_stmt->setString(5, dest_prt);
    prep_stmt->setString(6, blip);
    prep_stmt->execute();

    delete prep_stmt;
    delete con;

            }
        else

sql::mysql::MySQL_Driver *driver;
driver = sql::mysql::get_mysql_driver_instance();
sql::Connection *con;
    con = driver->connect("tcp://127.0.0.1:3306", "db", "password");
sql::PreparedStatement *prep_stmt;
    prep_stmt = con->prepareStatement("INSERT INTO db(srcIP, srcCountry, destIP, destHost, destPort, blIP) VALUES (?, ?, ?, ?, ?, ?)");

    prep_stmt->setString(1, src_ip);
    prep_stmt->setString(2, country_code);
    prep_stmt->setString(3, dest_ip);
        prep_stmt->setString(4, he->h_name);
    prep_stmt->setString(5, dest_prt);
    prep_stmt->setString(6, blip);
    prep_stmt->execute();

    delete prep_stmt;
    delete con;

编译：

g ++ sql.c -o sql -I / usr / include -I / usr / include / mysql -I / usr / include / mysql ++ -I / usr / local / include -I / usr / local / include / cppconn -lmysqlcppconn -lmysql ++ -lstdc ++ -lmysqlpp -lmysqlclient

并且总是在第二组MySQL驱动程序上得到错误：

错误：未在此范围内声明'driver'

Answer 1

仅基于我所看到的内容，看起来您在希望成为其他案例一部分的陈述中缺少大括号。如果你这样做：

if (x)
{
   // do something
}
else
   Foo* foo = new foo();
   foo->someFunction();

您将在读取foo->someFunction();的行上收到错误，因为else只包含一个没有大括号的语句，之后foo超出范围。你需要这样做：

if (x)
{
   // do something
}
else
{
   Foo* foo = new foo();
   foo->someFunction();
}

错误：＆＃39;驱动程序＆＃39;在这方面没有申明

1 个答案: