如何利用MySQL和C++開發一個簡單的檔案加密功能

CREATE DATABASE file_encryption;
USE file_encryption;

CREATE TABLE files (
id INT AUTO_INCREMENT PRIMARY KEY,
name VARCHAR(100),
encrypted_data VARBINARY(5000)
);

#include <mysql_driver.h>
#include <mysql_connection.h>
#include <cppconn/statement.h>
#include <cppconn/prepared_statement.h>
#include <cppconn/resultset.h>

#include <iostream>
#include <fstream>

using namespace std;

int main() {
    // 创建数据库连接
    sql::mysql::MySQL_Driver* driver;
    sql::Connection* con;

    driver = sql::mysql::get_mysql_driver_instance();
    con = driver->connect("tcp://127.0.0.1:3306", "root", "password");

    // 选择数据库
    con->setSchema("file_encryption");

    // 读取文件内容
    ifstream inputFile("input.txt");
    string fileContent((istreambuf_iterator<char>(inputFile)), istreambuf_iterator<char>());

    // 加密文件内容
    string encryptedContent = encrypt(fileContent);

    // 将加密后的内容存入数据库
    sql::PreparedStatement* pstmt = con->prepareStatement("INSERT INTO files (name, encrypted_data) VALUES (?, ?)");
    pstmt->setString(1, "input.txt");
    pstmt->setString(2, encryptedContent);
    pstmt->execute();

    // 从数据库中读取加密后的内容
    sql::Statement* stmt = con->createStatement();
    sql::ResultSet* res = stmt->executeQuery("SELECT encrypted_data FROM files WHERE name = 'input.txt'");
    res->first();

    // 解密文件内容
    string decryptedContent = decrypt(res->getString("encrypted_data"));

    // 将解密后的内容保存到文件
    ofstream outputFile("output.txt");
    outputFile << decryptedContent;

    // 释放内存
    delete res;
    delete stmt;
    delete pstmt;

    // 关闭数据库连接
    delete con;

    return 0;
}