Reading and rereading a file with QXmlStreamReader

[wysota]

Why reset the file at all? Can't you continue reading from the place where you stopped?

[TheRonin]

Why reset the file at all? Can't you continue reading from the place where you stopped?

I'm not sure i can since i get the "unexpected end of file"-error when i don't reset. The same is true even if i reset the file or close and reopen it. The only way around this i've found is to create a new streamReader-derived object AND reset the QIODevice:

QFile file(fileName);
file.open(QFile::ReadOnly | QFile::Text);
 
Parser typeCheck; // type checker!
FileType type = typeCheck.getType(&file);
file.reset();
if (type == TypeA){
  Parser reader; // actual reading of the file
  if (!reader.read(&file)){
    cout << "uh oh." << endl;
  }
}else{
  cout << "bad file type." << endl;
}
file.close();

QFile file(fileName);
file.open(QFile::ReadOnly | QFile::Text);

Parser typeCheck; // type checker!
FileType type = typeCheck.getType(&file);
file.reset();
if (type == TypeA){
  Parser reader; // actual reading of the file
  if (!reader.read(&file)){
    cout << "uh oh." << endl;
  }
}else{
  cout << "bad file type." << endl;
}
file.close();

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Correct me if i'm wrong but this feels like a bug. According to the documentation, QXmlStreamReader::setDevice() is supposed to reset the reader's internal state. If that were true, then doing reset() on the IODevice and resetting the reader's device should work.

[wysota]

I'm not sure i can since i get the "unexpected end of file"-error when i don't reset.

Because you try reading from the beginning. You have to continue reading where you left off (after determining the internal type of the file).