qsqlite 存儲和展示一個blob字段的數據

qsqlite存儲一個blob字段

第一種,通過直接使用sql語句進行存儲:

    sql = QString("INSERT INTO phone_video_fragment_display (_id,thumbnail,name,video_fragment_id) VALUES(%1,:thumbnail,'%2',%3);")

                  .arg(i64_phone_video_fragment_display_max_id)

                  .arg("demo....")

                  .arg(i64_phone_video_fragment_max_id);

    query.prepare(sql);

        //示例圖片

    QFile o_demo_jpeg("demo.jpg");

    auto open_result = o_demo_jpeg.open(QIODevice::ReadOnly);

    auto ba_demo_jpeg = o_demo_jpeg.readAll();

    query.bindValue(":thumbnail",ba_demo_jpeg);

    qDebug() << query.boundValues();

    auto exe_result = query.exec();

    auto error = query.lastError();

    qDebug() << error.text();

如上將thumbnail 圖片存入數據庫

第二種,通過更上層的接口

QSqlTableModel提供的insertRecord

(QSqlTableModel關聯一個數據庫的一張表,對其進行顯示或者操作)

    QSqlRecord record;

    QSqlField _id("_id",QVariant::LongLong);

    _id.setValue(i64_phone_video_fragment_display_max_id);

    QSqlField image("thumbnail",QVariant::ByteArray);

    image.setValue(ba_demo_jpeg);

    QSqlField name("name",QVariant::String);

    name.setValue(QString::number(i64_phone_video_fragment_display_max_id));

    QSqlField video_fragment_id("video_fragment_id",QVariant::LongLong);

    video_fragment_id.setValue(i64_phone_video_fragment_max_id);

    record.append( _id );

    record.append( image );

    record.append( name );

    record.append( video_fragment_id );

    this->m_p_obj_phone_video_fragment_model->insertRecord( -1,record );

    this->m_p_obj_phone_video_fragment_model->select();

別忘了select提交所有更改並刷新ui

要展示一個blob字段,如上的圖片,我們需要自己子類化一個delegate的paint接口

void CPhoneVideoFragmentDelegate::paint(QPainter *painter, const QStyleOptionViewItem &option, const QModelIndex &index) const

{

    //列說明:0._id,1.圖片,2.名字,3.底層的視頻碎片id

    if(index.column() == 1)

    {

        auto ba_image = index.model()->data(index).toByteArray();

        auto image = QImage::fromData(ba_image);

        painter->drawImage(option.rect,image);

    } else {

        return (QStyledItemDelegate::paint(painter,option,index));

    }

    return ;

}