How to write filepath in ini's section with QSettings - c++

Question

I need to use filepath as a section name in ini file and I try to do it like this:
QSettings ini(iniPath, QSettings::IniFormat);
ini.beginGroup("C:\\Users\\Username\\Documents\\222.txt");
ini.setValue(attributeName, attributeValue);
...
ini.endGroup();
Then I try to read values from this section:
QSettings ini(iniPath, QSettings::IniFormat);
ini.beginGroup("C:\\Users\\Username\\Documents\\222.txt");
auto allKeys = ini.allKeys();
for (auto& key: allKeys)
{
QString val = ini.value(key);
...
}
ini.endGroup();
But in the output file I can see just "[C%3AUsers%5CUsername%5CDocuments%5C222.txt]" as name of section. And most importantly that QSettings can't find this section when reads ini file, allKeys variable is always empty.
What could be the problem? Thanks.

Answer 1

Look at the QSettings::Format documentation:
QSettings always treats backslash as a special character and provides no API for reading or writing such entries.

Answer 2

Use QDir::fromNativeSeparators() for the section name. When you read back, just use the path as is (all Qt classes support it) or covert it to the Windows-style with QDir::toNativeSeparators().

Answer 3

It was my mistake. The code in my question is a little bit simplified. Code for writing and reading is located in methods "save" and "load". I Feel myself rather silly :( The problem was in the difference between input parameters in "save" and "load" methods. In "save" method input string was "C:\Users\Username\Documents\222.txt" and in "load" method it was "C:/Users/Username/Documents/222.txt" so when I tried to read the settings in "load" method QSettings didn't can find the section.
As I understand it QSettings escapes special characters like "\" with "%" symbol. And "/" symbol QSettings uses for making nestings. So I decide to use paths like "C:\Users\Username\Documents\222.txt" as is. It works fine. Thank you all.