#qt

头文件

``` cpp
#ifndef TESTFILEIO_H
#define TESTFILEIO_H

#include <QObject>

class TestFileIO : public QObject
{
    Q_OBJECT
public:

    static TestFileIO& instance() {
        static TestFileIO _instance;
        return _instance;
    }

    explicit TestFileIO(QObject *parent = nullptr);
    void writeToFile(const QString &fileName, const QString &text);

signals:
};

#endif // TESTFILEIO_H

```

cpp文件

``` cpp
#include "testfileio.h"
#include <QFile>
#include <QTextStream>

TestFileIO::TestFileIO(QObject *parent)
    : QObject{parent}
{}

void TestFileIO::writeToFile(const QString &fileName, const QString &text) {
    QFile file(fileName);
    if (!file.open(QIODevice::WriteOnly)) {
        qWarning("Cannot open file for writing.");
        return;
    }

    QTextStream out(&file);
    out << text;
    file.close();
}

```