将 MySQL 连接到 C++ 控制台应用程序和简单的登录系统

Question

I'd like to make simple login system in C++ Console Application with MySQL, and if login details are correct, it should execute my actual code.

How can that be done?

If possible, i'd also like to add so, when user login's for the first time, to store his HWID in database so no one else can login with same login credentials.

Thanks in advance, I am new to C++ programming and I don't really know what should I do:)

Answer 1

Here's a simple example of a login system:

#include <iostream>
#include <vector>
#include <map>
#include <string>

using std::cout;
using std::cin;
using std::string;
using std::vector;

struct Login_Info
{
    string name;
    unsigned int  id;
};

int main()
{
    vector<Login_Info> user_database;
    string user_name;
    cout << "Enter User's name:";
    getline(cout, user_name);
    unsigned int user_id = 0U;
    cout << "\nEnter User's ID: ";
    cin >> user_id;
    Login_Info user_info;
    user_info.name = user_name;
    user_info.id   = user_id;
    // Insert the User's info into the database.
    user_database.push_back(user_info);

    return EXIT_SUCCESS;
}

Searching and comparing are left as an exercise for the OP or Reader.

Edit 1: Index tables
Let's move the info I/O into the struct , then focus on building the database.

struct Login_Info
{
    string       name;
    unsigned int id;
    void  input_from_console(std::ostream& console_output_stream,
                             std::istream& console_input_stream);
};

void Login_Info::input_from_console(std::ostream& console_stream)
{
    console_output_stream << "Enter User's name: ";
    getline(console_input_stream, name);
    if (name.empty())
    {
        id = 0;
    }
    else
    {
        console_output_stream << "\nEnter User ID: ";
        console_input_stream >> id;
    }
}

int main()
{
    vector<Login_Info> user_database;
    std::map<unsigned int, unsigned int> index_by_id;
    Login_Info         user_info;
    while (true)
    {
        user_info.input_from_console(cout, cin);
        if (user_info.name.empty())
        {
            break;
        }
        unsigned int vector_index = user_database.size();
        user_database.push_back(user_info);  
        index_by_id[user_info.id] = vector_index;
    }
    return EXIT_SUCCESS;
}

The above program builds a database using std::vector , and creates an index table using std::map .

The User's name with ID == 5, can be found by:

Login_Info user_info;
const unsigned int vector_index = index_by_id[5];
user_info = database[vector_index];  
cout << "User #5 is: " << user_info.name << "\n";