Reading a text file

[anh5kor]

Hello

In my Project I am creating a LogReport.txt. Which maintain a Report like below
ECU->USS
Sensor Time Data
USS1 17:45:51 0x0,0xff,0x0,0x0
USS2 17:45:52 0x0,0x0,0xff,0x0
USS3 17:45:53 0x0,0x0,0x0,0x0
USS4 17:45:54 0x0,0xff,0x0,0x0
USS->ECU
Sensor Time Data
USS1 17:45:51 0x0,0x0,0x0,0x0
USS2 17:45:52 0x0,0xff,0x0,0x0
USS3 17:45:53 0x0,0xff,0x0,0x0
USS4 17:45:54 0x0,0x0,0xff,0x0
------
------
And so on until the code run.
Now once I stop my code I have to read back same data on button click.
Suppose on first click I have to read 17:45:51 0x0 0xff 0x0 0x0 and second click 17:45:52 0x0 0x0 0xff 0x0 and so on.
Can any one let me know how can I read each line with five different column.

Writefile


file->setFileName("LogReport.txt");
file->open(QIODevice::WriteOnly | QIODevice::Text);
QTextStream stream(file);
int index = 0;

stream << "ECU->USS\n";
stream <<"Sensor"<<" "<<"Time"<<" "<<"Data"<<endl;
for(int i = 0;i<12;i++)
{
stream << "USS"<<i+1<<" ";

stream<<time_log_ecu2uss[i];
if(i<9)
{
stream<<" ";
}
else
{
stream<<" ";
}

for(int j = 0;j<4;j++)
{

stream<<("0x"+QString::number(Data_ecu2uss[index],16));
if(j<3)
{
stream<<",";
}
index++;
}

stream<<endl;
}

index = 0 ;
stream << "USS->ECU\n";
stream <<"Sensor"<<" "<<"Time"<<" "<<"Data"<<endl;
for(int i = 0;i<12;i++)
{
stream << "USS"<<i+1<<" ";
stream<<time_log_uss2ecu[i];
if(i<9)
{
stream<<" ";
}
else
{
stream<<" ";
}
for(int j = 0;j<4;j++)
{
stream<<("0x"+QString::number(Data_uss2ecu[index],16));
if(j<3)
{
stream<<",";
}
index++;
}
stream<<endl;
}

stream<<"************************************************** ****************"<<endl;

}

[Lesiok]

Use QTextStream::readLine

[anh5kor]

For readline it will read whole Line like


QString line = in.readLine();
qDebug()<<"line"<<line;

o/p:- "USS1 12:17:52 0x0 0x0 0x0 0x0"
Now how can I extract each text and store in array.
it is better if I read 12:17:52 ,0x0,0x0,0x0,0x0 separately every time.

[wysota]

So what is stopping you from doing that?

[anh5kor]

So I have button in my gui when it click I should read First line.
Again if I click I should read second line and so on but
when I click first time I am getting the first line
but when clicking on second time I am getting nothing.



QTextStream in(file);
QString line = in.readLine();
qDebug()<<"line"<<line

o/p:-USS1 15:14:33 0x0 0x0 0x0 0x5d (on first click)
" "(on second click)

It seem it is not going to second line

[wysota]

Show some concrete code please.

[anh5kor]

void ui_logging::Button_clicked()
{

QTextStream in(file);
QTextStream stream(file);
QString str1;


for(int i = 0;i<6;i++)
{

in>>str1;
qDebug()<<str1;

}

}

O/p:First Click->USS1 15:14:33 0x0 0x0 0x0 0x5d
2nd Click->"" "" "" "" "" ""
3rd click->"" "" "" "" "" ""
--------so on
So on every click I have to read 6 string and on another click read the next 6 string but I am only getting the data on First click only and from
next click getting Null

[wysota]

What is file? Where do you open it? Why are you creating two text streams on it? Why do you do that every time the slot is called?

[anh5kor]

ui_logging::ui_logging()//constructor
{
QFile *file = new QFile();
}
openwrite_logfile() //call at start button
{
file->setFileName("LogReport.txt");
file->open(QIODevice::WriteOnly | QIODevice::Text);
}
openread_logfile()//call at stop button
{
file->open(QIODevice::ReadOnly | QIODevice::Text);
}

void ui_logging::Button_Clicked //display data on read button clicked
{

QTextStream in(file);
for(int i = 0;i<10;i++)
{

in>>str1;
qDebug()<<str1;

}

}


I don't have any idea to declare QTextStream in(file) as globally

[wysota]

You are aware 'file' variable from line #3 and the one from line #18 are different variables, right?

One warning from me -- when asked for code if you ever again post pseudo-code then I will either ignore your post or give you a pseudo-answer comparable to your pseudo-code.

[anh5kor]

I think till now you understand what exactly I am asking for.
I have recognize the Problem and my problem is in below code


void ui_logging::Button_Clicked()
{

QTextStream in(file); //My Problem is here on every click I am creating the object again and again

for( i = 0;i<10;i++)
{

in>>str1;
qDebug()<<str1;

}
int n = in.pos();


}

Do you have any solution for the above.

[wysota]

The file is probably a class member variable. Make the stream a class member variable as well.