how to read one line use the QSerialPort

[xiongxiongchuan]

void MainWindow::readData()
{
	QByteArray data = serial->readAll();
 
	infoConsole->PutData(data);
 
	if(data.count()>0 &&data.endsWith('\n'))
	{
		infoConsole->PutData(data);
 
 
		infoConsole->PutData(readjson(data,"msg"));
		tempPanel->setNumber(readjson(data,"temp").toFloat());
		tempPanel->setUnit("Centigrade");
 
		humPanel->setNumber(readjson(data,"Humidity").toFloat());
		humPanel->setUnit("%");
 
	}
}
 
 
QString MainWindow::readjson(QByteArray data,QString jasonName)
{
	qDebug()<<data<<"\n";
	QJsonParseError json_error;
	QJsonDocument parse_doucment = QJsonDocument::fromJson(data, &json_error); 
	if(json_error.error == QJsonParseError::NoError) 
	{
		if(parse_doucment.isObject())  
		{
			 QJsonObject obj = parse_doucment.object(); 
			 if (obj.contains(jasonName))
			 {
				  QJsonValue objectValue = obj.take(jasonName);
				  if(objectValue.isString())
				  {
					  return objectValue.toString();
				  }
			 }
		}
	}
 
	return NULL;
}

void MainWindow::readData()
{
	QByteArray data = serial->readAll();
	
	infoConsole->PutData(data);
	
	if(data.count()>0 &&data.endsWith('\n'))
	{
		infoConsole->PutData(data);
	 
		
		infoConsole->PutData(readjson(data,"msg"));
		tempPanel->setNumber(readjson(data,"temp").toFloat());
		tempPanel->setUnit("Centigrade");

		humPanel->setNumber(readjson(data,"Humidity").toFloat());
		humPanel->setUnit("%");
		
	}
}


QString MainWindow::readjson(QByteArray data,QString jasonName)
{
	qDebug()<<data<<"\n";
	QJsonParseError json_error;
	QJsonDocument parse_doucment = QJsonDocument::fromJson(data, &json_error); 
	if(json_error.error == QJsonParseError::NoError) 
	{
		if(parse_doucment.isObject())  
		{
			 QJsonObject obj = parse_doucment.object(); 
			 if (obj.contains(jasonName))
			 {
				  QJsonValue objectValue = obj.take(jasonName);
				  if(objectValue.isString())
				  {
					  return objectValue.toString();
				  }
			 }
		}
	}

	return NULL;
}

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and the data is {"Temp":{"temp":27.00000,"unit":"centigrade"},"Hum idity":{"humidity":60.00000,"unit":"%"}}

i use the

connect(serial, SIGNAL(readyRead()), this, SLOT(readData()));

connect(serial, SIGNAL(readyRead()), this, SLOT(readData()));

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i also use the QSerialPort ReadLine(), it dosen't work at all ;


i am waiting for your answer!
thanks!

[xiongxiongchuan]

anyone online can help me ?please

[anda_skoa]

Data arrives in blocks. Check if a block contains the line break. if it does not, store the data and wait for the next block.

Cheers,
_

[xiongxiongchuan]

i have tried many ways to solve this problem ,but always failed to read the whole line,can you tell more information and more specify in code ways,thank you!

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Added after 44 minutes:

QSerialPort::readline() dosen't work

[xiongxiongchuan]

QSerialPort::readline() dosen't work ! how to read one line ?