Big problem in reading&writing binary files
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Hi,
On your QFile pointer you could set a QByteArray and check out that class to define how do you need that data from the file. The fromHex en toHex jump to mind in your case.
Greetz -
Thanks for your reply,
look, this is my code :for writing:
[code]QString strToWrite = ui->User_signUp->text()+ui->Pass_signUp->text();
QFile fileToWrite("users.dat");
QDataStream dataStreamWriter(&fileToWrite);
fileToWrite.open(QIODevice::WriteOnly);
dataStreamWriter << strToWrite;
fileToWrite.close();[/code]
and for reading:
[code]
QString strToRead= "";
QFile fileToRead("users.dat");
QDataStream dataStreamReader(&fileToRead);
fileToRead.open(QIODevice::ReadOnly);
dataStreamReader >> strToRead;
fileToRead.close();qDebug() << strToRead;
[/code]
but in this case problem is that qDebug does'nt work.
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Hi and welcome to devnet,
Is it a typo or are you really writing to users.bin and reading from file.bin ?
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Sorry i change the code with QByteArray,
for writing:
[code]
QByteArray ar=ui->User_signUp->text().toUtf8()+"%"+ ui->Pass_singUp->text().toUtf8()+"$";
QFile file("users.dat");
file.open(QIODevice::WriteOnly | QIODevice::Append );
file.write(ar);[/code]
this code writes the usernames and passwords correctly
Now assume that i want to search a specified String(username) in my file, I think i can do this by using 2 QByteArrays, one for the username (which user has entered) and another for the file which reads whole file.
but i don't know how i can use them. could you help me? -
Are you thinking about QByteArray::contains ?