Windows 7 and Windows 10, QSettings read registory REG_DWORD keys, can not get the values

[Frankkon]

Windows 7 and Windows 10, QSettings read registory REG_DWORD keys, can not get the values,but other type keys can read well, eg. REG_SZ.
code as below:
void MainWindow::on_pushButton_clicked()
{
ui->listWidget->clear();
QString str = ui->lineEdit->text();
QSettings reg(str, QSettings::Registry64Format);
QStringList keyList=reg.childKeys();
foreach(QString key, keyList)
{
QString keyvalue=reg.value(key).toString();
ui->listWidget->addItem(key + " = " + keyvalue);
}
}
output as below:

[jsulm]

@Frankkon said in Windows 7 and Windows 10, QSettings read registory REG_DWORD keys, can not get the values:

reg.value(key).toString()

Did you try to print out reg.value(key)

qDebug() << reg.value(key);

You're converting it to string, but actually it is an integer number. You should convert to string like this:

QString::number(reg.value(key).toInt());

[Frankkon]

@jsulm Thank you very much. I do as you said, but it still not work well.
my debug code as below:
qDebug() << key << " = " << reg.value(key);
qDebug() << key << " = " << reg.value(key).toInt();
qDebug() << key << " = " << QString::number(reg.value(key).toInt());
the debug output as below:

but regedit tool shows as below:

can you help me? thank you.

[hskoglund]

Hi, unfortunately when registry keys contain slashes or backslashes QSettings does not work :-(
But you can still use old the old Win32 API, like this:

Add
LIBS += -ladvapi32
to your .pro file.

Add #include "windows.h" to your .cpp file.

And try something like this:

QSettings reg("HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows\\CurrentVersion\\SharedDLLs\\",QSettings::NativeFormat);

for (QString key : reg.childKeys())
{
    key = key.replace("/","\\");    // replace back to backslashes to keep Windows happy
    DWORD dw = 0,sdw = sizeof(dw);  // dword value comes to dw
    ::RegGetValue(HKEY_LOCAL_MACHINE,L"Software\\Microsoft\\Windows\\CurrentVersion\\SharedDLLs",(LPCWSTR) key.constData(),RRF_RT_DWORD,NULL,&dw,&sdw);

    qDebug() << key << dw;
}

[Frankkon]

@hskoglund Thank you! Yes, the problom is “\” , I create a key like "aaa/bbb/ccc"， QSettings can work well on it. Thanks a lot.