where is cout in Qt Creator

[saa7_go]

You can replace cout with qDebug(),

#include <QDebug>
 
qDebug() << "Hello World";

#include <QDebug>

qDebug() << "Hello World";

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The output will be showed in the Application Output.

[tbscope]

No, that won't work either. All output is directed to stdout (or stderr), but a Qt Windows program never opens a console window unless you add a configuration option.

Add CONFIG += console in your .pro file
This will open a console window when you start your program.

[saa7_go]

No, that won't work either. All output is directed to stdout (or stderr), but a Qt Windows program never opens a console window unless you add a configuration option.

If you use gui module, and include QApplication header, the output from qDebug() will be showed in the Application Output (in Qt Creator).

Add CONFIG += console in your .pro file
This will open a console window when you start your program.

The problem is when you don't use event loop, console window will close immediately (when using Qt Creator). In windows, i usually add CONFIG += console in my .pro and the following line

#include <iostream>
#include <cstdlib>
 
using namespace std;
 
int main(int argc, char *argv[])
{
    cout << "Hello World!" << endl;
    system("PAUSE"); // <---
    return 0;
}

#include <iostream>
#include <cstdlib>

using namespace std;

int main(int argc, char *argv[])
{
    cout << "Hello World!" << endl;
    system("PAUSE"); // <---
    return 0;
}

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[pervlad]

QTextStream can be used too.

QTextStream out(stdout);
out << QString("Some text");

QTextStream out(stdout);
out << QString("Some text");

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[hqking1988]

thank you for your advice,it works out