doc/src/examples/htmlinfo.qdoc
author Alex Gilkes <alex.gilkes@nokia.com>
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/****************************************************************************
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**
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** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
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** All rights reserved.
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** Contact: Nokia Corporation (qt-info@nokia.com)
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**
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** This file is part of the documentation of the Qt Toolkit.
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**
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** $QT_BEGIN_LICENSE:LGPL$
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** No Commercial Usage
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** This file contains pre-release code and may not be distributed.
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** You may use this file in accordance with the terms and conditions
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** contained in the Technology Preview License Agreement accompanying
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** this package.
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**
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** GNU Lesser General Public License Usage
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** Alternatively, this file may be used under the terms of the GNU Lesser
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** General Public License version 2.1 as published by the Free Software
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** Foundation and appearing in the file LICENSE.LGPL included in the
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** packaging of this file.  Please review the following information to
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** ensure the GNU Lesser General Public License version 2.1 requirements
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** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
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**
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** In addition, as a special exception, Nokia gives you certain additional
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** rights.  These rights are described in the Nokia Qt LGPL Exception
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** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
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**
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** If you have questions regarding the use of this file, please contact
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** Nokia at qt-info@nokia.com.
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**
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**
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**
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**
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**
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**
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**
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**
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** $QT_END_LICENSE$
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**
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****************************************************************************/
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/*!
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    \example xml/htmlinfo
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    \title XML HTML Info Example
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    The XML HTML Info example provides a simple command line utility that
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    scans the current directory for HTML files and prints statistics about
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    them to standard out.
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    \note Standard out is redirected on some platforms. On Symbian using Open
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    C \c stdout is by default directed to the console window, but this window
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    may not always be visible. To redirect to a file instead, locate the \c
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    c:\\system\\data\\config.ini file (on either the emulator or the device)
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    and change \c STDOUT to point to \c MEDIA4. This will redirect the console
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    to \c c:\\system\\data\\out.txt.
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    The files are parsed using a QXmlStreamReader object. If the file does
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    not contain a well-formed XML document, a description of the error is
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    printed to the standard error console.
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    \section1 Basic Operation
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    The main function of the example uses QDir to access files in the current
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    directory that match either "*.htm" or "*.html". For each file found,
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    the \c parseHtmlFile() function is called.
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    Reading XML is handled by an instance of the QXmlStreamReader class, which
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    operates on the input file object:
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    \snippet examples/xml/htmlinfo/main.cpp 0
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    The work of parsing and the XML and extracting statistics is done in a
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    while loop, and is driven by input from the reader:
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    \snippet examples/xml/htmlinfo/main.cpp 1
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    If more input is available, the next token from the input file is read
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    and parsed. The program then looks for the specific element types,
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    "title", "a", and "p", and stores information about them.
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    When there is no more input, the loop terminates. If an error occurred,
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    information is written to the standard out file via a stream, and the
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    example exits:
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    \snippet examples/xml/htmlinfo/main.cpp 2
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    If no error occurred, the example prints some statistics from the data
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    gathered in the loop, and then exits.
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*/