C++ How can I parse the data sent from the serial port?

mangekoyu

I am trying to read ID over serial port. When I send my WT+12300 command via serial port. I am getting ID data. But it comes all the time and it doesn't come as parsed. "WT+,ID,2,3,4,5,6,ASDSA,1,\r\nWT+,ID,2,3,4,5,6,ASDSA,1,\r\nWT+,ID,2, I get it as 3,4,5,6,ASDSA,1,\r\n... and it keeps going. I just want to take the ASDSA part and display it with a qlabel. How can I do that?
here is function

void productDetail::on_pushButton_clicked()
{

    if (serial.begin(QString("COM6"), 9600, 8, 0, 1, 0, false)  )
 {

      QString sendWC= "WR+11300";
      serial.send(sendWC);
       QString serialID = serial.getString();
       serialID = serialID.simplified();
       ui->idLabel->setText(serialID);
       qDebug()<< serialID;

  }

JonB

@mangekoyu said in C++ How can I parse the data sent from the serial port?:

I just want to take the ASDSA part

We don't what the ASDA "part" might mean to you....
In any case, use either QString.indexOf() or QString::match() to find whatever it is you want in the string.

mangekoyu

@JonB I can print whatever I want on that part. To try, I randomly defined ASDSA to ID. my goal is to get the id part there. Could you please write an example?

JonB

@mangekoyu
You do not define what you mean by "take the ASDSA part", maybe you mean the number which comes as the next item after ASDSA,, who knows, I'm not going to guess..... In any case use either of the methods I suggested.

mangekoyu

@JonB I just want to take the 'ASDAS' part from the data I received and print it on a label. The only ASDAS part I need from the data I received.

JonB

@mangekoyu
I don't know what "the 'ASDAS' part" actually is, I have asked you twice, given you an example of what you might mean, and still no answer. So I leave that to you, I'm not going to ask again. If all you want is ASDA on a label go label->setText("ASDA").

JonB

@mangekoyu
Someone has now suggested you mean "The 8th comma-separated item., counting from 0, on each line". They are obviously a better mind-reader than I, since I did not get that.....

So.... sounds like you want to

First, QString::split() your input string on \r\n, to get a list of lines.
Then, split again on , to get a list of "items", and you want [7].

mangekoyu

@JonB Thank You for help. It worked.

mpergand

An easier method:

QString serial="WT+,ID,2,3,4,5,6,ASDSA,1,\r\nWT+,ID,2,3,4,5,6,ASDSA,1,\r\nWT+,ID,2";
QString id = serial.section(',', 7,7);
qDebug()<<id;  // id = ASDSA

Kent-Dorfman

and it is still wrong because you cannot make assumptions about the content of input streams with regard to completeness. you have to read in and accumulate data until you have enough to parse, then parse what is available and discard what has been successfully processed. Maybe your serial IO is line buffered...maybe it is not. Don't make the assumption that any single serial read contains complete parseable data.