C++连接Mysql数据库，mysql_real_connect总是报错：访问内存冲突

<code> #include <winsock.h>#include <iostream>#include <string>#include <mysql.h>using namespace std;#pragma comment(lib, "ws2_32.lib")#pragma comment(lib, "libmysql.lib")//单步执行，不想单步执行就注释掉#define STEPBYSTEPint main() {    cout << "****************************************" << endl;#ifdef STEPBYSTEP    system("pause");#endif    //必备的一个数据结构    MYSQL mydata;    //初始化数据库    if (0 == mysql_library_init(0, NULL, NULL)) {        cout << "mysql_library_init() succeed" << endl;    } else {        cout << "mysql_library_init() failed" << endl;        return -1;    }#ifdef STEPBYSTEP    system("pause");#endif    //初始化数据结构    if (NULL != mysql_init(&mydata)) {        cout << "mysql_init() succeed" << endl;    } else {        cout << "mysql_init() failed" << endl;        return -1;    }#ifdef STEPBYSTEP    system("pause");#endif    //在连接数据库之前，设置额外的连接选项    //可以设置的选项很多，这里设置字符集，否则无法处理中文    if (0 == mysql_options(&mydata, MYSQL_SET_CHARSET_NAME, "gbk")) {        cout << "mysql_options() succeed" << endl;    } else {        cout << "mysql_options() failed" << endl;        return -1;    }#ifdef STEPBYSTEP    system("pause");#endif    //连接数据库    if (NULL            != mysql_real_connect(&mydata, "localhost", "root", "test", "test",                    3306, NULL, 0))            //这里的地址，用户名，密码，端口可以根据自己本地的情况更改            {        cout << "mysql_real_connect() succeed" << endl;    } else {        cout << "mysql_real_connect() failed" << endl;        return -1;    }#ifdef STEPBYSTEP    system("pause");#endif    //sql字符串    string sqlstr;    //创建一个表    sqlstr = "CREATE TABLE IF NOT EXISTS user_info";    sqlstr += "(";    sqlstr +=            "user_id INT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY COMMENT 'Unique User ID',";    sqlstr +=            "user_name VARCHAR(100) CHARACTER SET gb2312 COLLATE gb2312_chinese_ci NULL COMMENT 'Name Of User',";    sqlstr +=            "user_second_sum INT UNSIGNED NOT NULL DEFAULT 0 COMMENT 'The Summation Of Using Time'";    sqlstr += ");";    if (0 == mysql_query(&mydata, sqlstr.c_str())) {        cout << "mysql_query() create table succeed" << endl;    } else {        cout << "mysql_query() create table failed" << endl;        mysql_close(&mydata);        return -1;    }#ifdef STEPBYSTEP    system("pause");#endif    //向表中插入数据    sqlstr =            "INSERT INTO user_info(user_name) VALUES('公司名称'),('一级部门'),('二级部门'),('开发小组'),('姓名');";    if (0 == mysql_query(&mydata, sqlstr.c_str())) {        cout << "mysql_query() insert data succeed" << endl;    } else {        cout << "mysql_query() insert data failed" << endl;        mysql_close(&mydata);        return -1;    }#ifdef STEPBYSTEP    system("pause");#endif    //显示刚才插入的数据    sqlstr = "SELECT user_id,user_name,user_second_sum FROM user_info";    MYSQL_RES *result = NULL;    if (0 == mysql_query(&mydata, sqlstr.c_str())) {        cout << "mysql_query() select data succeed" << endl;        //一次性取得数据集        result = mysql_store_result(&mydata);        //取得并打印行数        int rowcount = mysql_num_rows(result);        cout << "row count: " << rowcount << endl;        //取得并打印各字段的名称        unsigned int fieldcount = mysql_num_fields(result);        MYSQL_FIELD *field = NULL;        for (unsigned int i = 0; i < fieldcount; i++) {            field = mysql_fetch_field_direct(result, i);            cout << field->name << "\t\t";        }        cout << endl;        //打印各行        MYSQL_ROW row = NULL;        row = mysql_fetch_row(result);        while (NULL != row) {            for (int i = 0; i < fieldcount; i++) {                cout << row[i] << "\t\t";            }            cout << endl;            row = mysql_fetch_row(result);        }    } else {        cout << "mysql_query() select data failed" << endl;        mysql_close(&mydata);        return -1;    }#ifdef STEPBYSTEP    system("pause");#endif    //删除刚才建的表    sqlstr = "DROP TABLE user_info";    if (0 == mysql_query(&mydata, sqlstr.c_str())) {        cout << "mysql_query() drop table succeed" << endl;    } else {        cout << "mysql_query() drop table failed" << endl;        mysql_close(&mydata);        return -1;    }    mysql_free_result(result);    mysql_close(&mydata);    mysql_server_end();    system("pause");    return 0;}</code>