QT 读取txt文件的几种方法

 

废话不说直接上代码

１．

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QString displayString; QFile file("/home/alvin/text.txt"); if(!file.open(QIODevice::ReadOnly | QIODevice::Text)) {     qDebug()<<"Can't open the file!"< } while(!file.atEnd()) {     QByteArray line = file.readLine();     QString str(line);     qDebug()<< str;     displayString.append(str); }    ui->textEdit->clear();    ui->textEdit->setPlainText(displayString);

 ２．

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QString displayString;     QFile file("/home/alvin/text.txt");      if (!file.open(QIODevice::ReadOnly | QIODevice::Text))          return;        QTextStream in(&file);      QString line = in.readLine();        while (!line.isNull())      { //         process_line(line);          line = in.readLine();          displayString.append(line);      }        ui->textEdit->clear();        ui->textEdit->setPlainText(displayString);

 ３．

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QString displayString; QFile file("/home/alvin/text.txt");  if(!file.open(QIODevice::ReadWrite | QIODevice::Text)) {      qDebug()<<"Can't open the file!"<  }  QTextStream stream(&file);  QString line_in;  stream.seek(file.size());//将当前读取文件指针移动到文件末尾  int count = 0;  while(count < 10)  {      stream << QObject::trUtf8("新建行:") <<++count<<"/n";  }  stream.seek(0);//将当前读取文件指针移动到文件开始  while( !stream.atEnd())  {      line_in = stream.readLine();      displayString.append(line_in);      qDebug() << line_in;  }  ui->textEdit->clear();  ui->textEdit->setPlainText(displayString);

 以上是三种ＱＴ读取文件的方法，

源码在这里自行下载查看

1	https://pan.baidu.com/s/1pKIwzHL

 

Txt文件的写入的方法

    QFile f("./test.txt");
    if(!f.open(QIODevice::WriteOnly | QIODevice::Text))
    {
        cout << "Open failed." << endl;
        return data;
    }

    QTextStream txtOutput(&f);
    QString s1("123");
    quint32 n1(123);

    txtOutput << QString::fromStdString(str_json) << endl;
    txtOutput << n1 << endl;

    f.close();