QTextStream with QString

[kiker99]

Hello,

i don't quite understand how QTextStream works together with QStrings. I've got this code:

QString s;
QTextStream ts(&s);
ts<<11<<" Freunde";
std::cout<<"1."<<ts.readAll().toStdString()<<'\n'<<"2."<<s.toStdString();

QString s;
QTextStream ts(&s);
ts<<11<<" Freunde";
std::cout<<"1."<<ts.readAll().toStdString()<<'\n'<<"2."<<s.toStdString();

To copy to clipboard, switch view to plain text mode 

That produces this output:
1.11 Freunde

Why doesn't QTextStream write to the String, as intended? I would be happy with this behaviour, too, but why do I have to specify a string as an argument with the constructor? Is there a function that needs to be called? I didn't find one and in the examples it works without one - but the examples work with devices rather than QStrings.
Thanks.

[munna]

This might help to understand things better.

[kiker99]

This might help to understand things better.

The Qt Documentation is my first ressource if I want to look up something, so I've read that already. I don't see an answer to my question in there.

[jpn]

Try calling QTextStream::flush() to flush the buffered data waiting to be written.

[gfunk]

That's weird, when I run it, the output I get is:

1.11 Freunde
2.11 Freunde

which is what I expect. (Running WinXP, Qt 4.1.3)
The docs say that QTextStream::flush() has no effect when QTextStream operates on a string... Maybe your cout just needs to be flushed? weird.

[kiker99]

Thanks, but neither

QString s;
QTextStream ts(&s);
ts<<11<<" Freunde";
ts.flush();
std::cout<<"1."<<ts.readAll().toStdString()<<'\n'<<"2."<<s.toStdString();

QString s;
QTextStream ts(&s);
ts<<11<<" Freunde";
ts.flush();
std::cout<<"1."<<ts.readAll().toStdString()<<'\n'<<"2."<<s.toStdString();

To copy to clipboard, switch view to plain text mode 

nor

QString s;
QTextStream ts(&s);
ts<<11<<" Freunde";
std::cout<<"1."<<ts.readAll().toStdString()<<'\n'<<"2."<<s.toStdString();
std::cout.flush();

QString s;
QTextStream ts(&s);
ts<<11<<" Freunde";
std::cout<<"1."<<ts.readAll().toStdString()<<'\n'<<"2."<<s.toStdString();
std::cout.flush();

To copy to clipboard, switch view to plain text mode 

nor a combination ob both helps. But perhaps we are on the right track
I'm using Qt 4.1.4 on Linux.

[gfunk]

Why "2." doesn't even show in your output?
What happens if you split the cout into two lines?

std::cout<<"1."<<ts.readAll().toStdString()<<'\n';
std::cout <<"2."<<s.toStdString();

[jpn]

What about if you try to use qDebug() for outputting?

#include <QtDebug>
qDebug() <<"1."<<ts.readAll()<<'\n'<<"2."<<s;

#include <QtDebug>
qDebug() <<"1."<<ts.readAll()<<'\n'<<"2."<<s;

To copy to clipboard, switch view to plain text mode