XML Stream Lint Example

Basic Operation

The main function of the example opens the file specified by the user for input (inputFile), and it uses QFile to access the standard output file.

Reading XML is handled by an instance of the QXmlStreamReader class, which operates on the input file object; writing is handled by an instance of QXmlStreamWriter operating on the output file object:

     QXmlStreamReader reader(&inputFile);
     QXmlStreamWriter writer(&outputFile);

The work of parsing and rewriting the XML is done in a while loop, and is driven by input from the reader:

     while (!reader.atEnd())
     {
         reader.readNext();

         if (reader.error())
         {
             errorStream << XmlStreamLint::tr(
                            "Error: %1 in file %2 at line %3, column %4.\n").arg(
                                reader.errorString(), inputFilePath,
                                QString::number(reader.lineNumber()),
                                QString::number(reader.columnNumber()));
             return ParseFailure;

If more input is available, the next token from the input file is read and parsed. If an error occurred, information is written to the standard error file via a stream, and the example exits by returning a non-zero value from the main function.

         } else
             writer.writeCurrentToken(reader);
     }

For valid input, the writer is fed the current token from the reader, and this is written to the output file that was specified when it was constructed.

When there is no more input, the loop terminates, and the example can exit successfully.