file.cpp

Go to the documentation of this file.

// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
 
#include <QFile>
#include <QTextStream>
 
static void process_line(const QByteArray &)
{
}
 
static void process_line(const QString &)
{
}
 
static void noStream_snippet()
{
//! [0]
    QFile file("in.txt");
    if (!file.open(QIODevice::ReadOnly | QIODevice::Text))
        return;
 
    while (!file.atEnd()) {
        QByteArray line = file.readLine();
        process_line(line);
    }
//! [0]
}
 
static void readTextStream_snippet()
{
//! [1]
    QFile file("in.txt");
    if (!file.open(QIODevice::ReadOnly | QIODevice::Text))
        return;
 
    QTextStream in(&file);
    while (!in.atEnd()) {
        QString line = in.readLine();
        process_line(line);
    }
//! [1]
}
 
static void writeTextStream_snippet()
{
//! [2]
    QFile file("out.txt");
    if (!file.open(QIODevice::WriteOnly | QIODevice::Text))
        return;
 
    QTextStream out(&file);
    out << "The magic number is: " << 49 << "\n";
//! [2]
}
 
static void writeDataStream_snippet()
{
    QFile file("out.dat");
    if (!file.open(QIODevice::WriteOnly))
        return;
 
    QDataStream out(&file);
    out << "The magic number is: " << 49 << "\n";
}
 
static void readRegularEmptyFile_snippet()
{
//! [3]
    QFile file("/proc/modules");
    if (!file.open(QIODevice::ReadOnly | QIODevice::Text))
        return;
 
    QTextStream in(&file);
    QString line = in.readLine();
    while (!line.isNull()) {
        process_line(line);
        line = in.readLine();
    }
//! [3]
}