[SOLVED] How can I override a text line in txt file.
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@ QFile file3(_filename3);
QTextStream out3(&file3);
if(!file3.open(QFile::WriteOnly)){
qDebug() << "could not open file for writing";
return;
}else{
QString item1 = ui->lineEdit_4->text();
QString item2 = ui->lineEdit_5->text();
out3 << item1 << "\r\n" ;
out3 << item2 << "\r\n";
out3 << _directory3;
file3.flush();
file3.close();
}
@I get three directories that appear in my lineEdits and write them in a text file.
When I change some directory on my LineEdit eg _directory3, it should be written in my text file to replace the old. Only what happens the following problem: If I select the directory that is mair than the old (more characters), when you print the text file, it not replaces the old completely. For example:
Old: C :/ Users / eng / Desktop / lineEditqt.txt
New: C :/ Users / eng / Desktop / qt.txt.
in my text file it is written:
C :/ Users / eng / Desktop / qt.txtitqt.txt
and not as it should be, it would be like this:
C :/ Users / eng / Desktop / qt.txtHow can I solve it?
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Hi,
One question first: is that the only content of your file ?
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In my txt file has just 3 paths that I can override.
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Hii
your given code is working right if i remove line 11.
i have doubt on line 11
What is this _directory3 ?
is this same as item1 or item2 ?
if yes How are you getting _directory3 ?
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Then you should just read the file line by line in e.g. a QStringList. Replace the line you modified in the QStringList and then overwrite the content of the original file with the content of the QStringList.
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Can you show me an example with this?
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Of reading a file line by line ?
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No. I don't now how to use QStringList in this case.
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Then please, take some time to read the documentation of this class.
One way:
@QStringList lines
//open file etc.
while(!steam.atEnd()) {
lines << stram.readLine();
} @There are also other way to do that e.g. using QString::split
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The solution was simpler than I imagined.
Simply put:
@if(!file3.open(QFile::ReadWrite | QFile::Truncate)){
qDebug() << "could not open file for writing";
return;@
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With that you don't just change one line like you ask for, you are overwriting everything.
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Yes, but I also rewrite those who have not been changed.
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if your problem is solved then make this title as SOLVED by adding [SOLVED] tag before the title.
