MySQL存入图片+Qt读入读出数据库中的图片_MySQL

create table `sfood`(
`name` varchar(255) not null,
`type` varchar(255) not null,
`material` varchar(255) not null,
`price` int(200) not null,
`feature` varchar(255) not null,
`image` longblob,
primary key(`name`)
)ENGINE=innodb default charset=gb2312;

QString select = "select * from sfood";

query.exec(select);

if（ query.next() ）

{

	QLabel *PicLabel = new QLabel();

QPixmap photo;

    photo.loadFromData(query.value(5).toByteArray(), "JPG"); //从数据库中读出图片为二进制数据，图片格式为JPG，然后显示到QLabel里

    PicLabel->setPixmap(photo);

    PicLabel->setScaledContents(true);

}

3.通过Qt往数据库中写入图片

query.exec("select * from sfood where name='"+nameEdit->text()+"'"); //我这里本段代码是添加菜品，该句是查询是否有该菜，按名字查询

    if(query.next())

    {

        QMessageBox::information(this,tr("警告"),tr("该菜已在数据库存储了"));

        db.Close();

        return;

    }

    query.prepare("insert into sfood(name,type,material,price,feature,image) values(?,?,?,?,?,?)");

    query.addBindValue(nameEdit->text());

    query.addBindValue(typeEdit->text());

    query.addBindValue(materialEdit->toPlainText());

    query.addBindValue(priceEdit->text());

    query.addBindValue(featureEdit->text());

    //接下来代码是保存图片到数据库

    imagePath.replace("\","/");  //转换路径格式,imagePath是图片文件的路径，我这里用的是绝对路径

    /*imagePath的获得方法可以这样写：

imagePath = QFileDialog::getOpenFileName(this, tr("Open File"),

                                                           "/home",

                                                          tr("Images (*.jpg)"));

    */

    QByteArray bytes;

    QBuffer buffer(&bytes);

    buffer.open(QIODevice::WriteOnly);

    pictureLabel->pixmap()->save(&buffer,"JPG");

    QByteArray data;

    QFile* file=new QFile(imagePath); //file为二进制数据文件名

    file->open(QIODevice::ReadOnly);

    data = file->readAll();

    file->close();

    QVariant var(data);

    query.addBindValue(var);

    query.exec();