基于Qt实现将BMP图像数据存入SQLite数据库

#include <QCoreApplication>
#include <QSqlDatabase>
#include <QSqlQuery>
#include <QFile>
#include <QDebug>

void saveBmpToDatabase(const QString &imagePath, const QString &databasePath)
 {

    QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE");
    db.setDatabaseName(databasePath);

    if (!db.open()) 
    {
        qDebug() << "无法打开数据库";
        return;
    }

    // 读取BMP图像文件
    QFile file(imagePath);
    if (!file.open(QIODevice::ReadOnly)) 
    {
        qDebug() << "无法打开图像文件";
        return;
    }

    QByteArray imageData = file.readAll();
    file.close();

    QSqlQuery query;
    query.exec("CREATE TABLE IF NOT EXISTS Images (id INTEGER PRIMARY KEY, data BLOB)");

    query.prepare("INSERT INTO Images (data) VALUES (:data)");
    query.bindValue(":data", imageData);

    if (!query.exec())
    {
        qDebug() << "插入图像数据失败";
    } else 
    {
        qDebug() << "图像数据插入成功";
    }

    db.close();
}

int main(int argc, char *argv[]) 
{
    QCoreApplication a(argc, argv);

    QString imagePath = "a.bmp";
    QString databasePath = "image.db";

    saveBmpToDatabase(imagePath, databasePath);

    return a.exec();
}

#include <QCoreApplication>
#include <QSqlDatabase>
#include <QSqlQuery>
#include <QFile>
#include <QDebug>

void loadBmpFromDatabase(const QString &outputPath, const QString &databasePath, int imageId)
 {

    QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE");
    db.setDatabaseName(databasePath);

    if (!db.open()) 
    {
        qDebug() << "无法打开数据库";
        return;
    }

    QSqlQuery query;
    query.prepare("SELECT data FROM Images WHERE id = :id");
    query.bindValue(":id", imageId);

    if (!query.exec()) 
    {
        qDebug() << "读取图像数据失败";
        return;
    }

    if (query.next())
     {
        QByteArray imageData = query.value(0).toByteArray();

        QFile file(outputPath);
        if (!file.open(QIODevice::WriteOnly)) {
            qDebug() << "无法打开输出文件";
            return;
        }

        file.write(imageData);
        file.close();

        qDebug() << "图像已保存到" << outputPath;
    } else {
        qDebug() << "未找到指定的图像";
    }

    db.close();
}

int main(int argc, char *argv[]) 
{
    QCoreApplication a(argc, argv);

    QString outputPath = "b.bmp";
    QString databasePath = "image.db";
    int imageId = 1; 

    loadBmpFromDatabase(outputPath, databasePath, imageId);

    return a.exec();
}