QByteArray 的外部与内部声明 [英] External vs internal declaration of QByteArray

问题描述

我目前在使用 QSerialPort 时遇到一些问题:当我使用一个示例中的函数时，它看起来像

I have currently some problems with the QSerialPort: When I am using the function from an example which looks like

QKeyEvent *e;
emit getData(e->text().toLocal8Bit());
connect(console, SIGNAL(getData(QByteArray)), this, SLOT(writeData(QByteArray)));
void MainWindow::writeData(const QByteArray &data)
{
    qDebug() << "Data is to write: " << data;
    serial->write(data);
}

然后接收设备可以处理数据.但是当我将函数 writeData() 更改为

then the receiving device can work with the data. But when I change the function writeData() to

void MainWindow::writeData(const QByteArray &data)
{
    QString a = "Q";
    QByteArray b = a.toLocal8Bit();
    serial->write(b);
}

接收设备无法处理接收到的数据.这两种方法的区别在哪里?
更新:我发现显然只有在键入字母后按 Enter 才能传输数据.不知何故，'\n' 在从 QString 到 QByteArray 的转换中丢失了.我怎样才能保留它?

the receiving device can not work with the received data. Where is the difference between those two approaches?
Update: I found out that apparently the data is only usefully transferred if I press Enter after typing the letters. Somehow the '\n' gets lost in the conversion from QString to QByteArray. How can I keep it?

推荐答案

你应该像这样在你的Qstring中添加一个回车

you should add an enter to your Qstring like this

QString a = "Q\x00D";

这篇关于QByteArray 的外部与内部声明的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！