void MainWindow::postrequest()
{
    QStringList postlist;
    for(int i=0; i<3; i++)
    {
        postlist.append("imgfile"+QString::number(i+1)+"=" + QString::number(i));
    }
    QString post = postlist.join("&");
    QHttpRequestHeader header("POST", "/index.php", 1, 1);
    header.addValue("Content-Type","application/x-www-form-urlencoded");
    header.addValue("Cache-Control", "no-cache");
    http->setHost("localhost");
    header.addValue("Host", "localhost");
    header.addValue("Accept","*/*");
    QByteArray postdata;
    postdata.append(post);
    http->request(header, postdata);
}