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/****************************************************************************
**
** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:FDL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Digia. For licensing terms and
** conditions see http://qt.digia.com/licensing. For further information
** use the contact form at http://qt.digia.com/contact-us.
**
** GNU Free Documentation License Usage
** Alternatively, this file may be used under the terms of the GNU Free
** Documentation License version 1.3 as published by the Free Software
** Foundation and appearing in the file included in the packaging of
** this file. Please review the following information to ensure
** the GNU Free Documentation License version 1.3 requirements
** will be met: http://www.gnu.org/copyleft/fdl.html.
** $QT_END_LICENSE$
**
****************************************************************************/
/*!
\group json
\title JSON Classes
*/
/*!
\page json.html
\title JSON Support in Qt
\ingroup qt-basic-concepts
\brief An overview over the JSON support in Qt.
\ingroup frameworks-technologies
\keyword JSON
Qt provides support for dealing with JSON data. JSON is a
format to encode object data derived from Javascript, but
now widely used as a data exchange format on the internet.
The JSON support in Qt provides an easy to use C++ API to parse,
modify and save JSON data. It also contains support for saving this
data in a binary format that is directly mmap'able and very fast to
access.
More details about the JSON data format can be found at \link json.org
and in \l{http://tools.ietf.org/html/rfc4627}{RFC-4627}.
\tableofcontents
\section1 Overview
JSON is a format to store structured data. It has 6 basic data types:
\list
\o bool
\o double
\o string
\o array
\o object
\o null
\endlist
Any value can be any of the above type. A boolean value is represented by the
strings true or false in JSON. JSON doesn't explicitly specify the valid range
for numbers, but the support in Qt is limited to the valid range for doubles.
A string can be any valid unicode string. An array is a list of values, and an
object is a dictionary of key/value pairs. All keys in an object are strings, and
an object can not contain any duplicated keys.
The text representation, of JSON encloses arrays in square brackets ([ ... ]) and
objects in curly brackets ({ ... }). The different entries in arrays and objects
are separated by commas. The separator between keys and values in an object is a
colon (:).
A simple JSON document encoding a person, its age, address and phone numbers could
look like:
\code
{
"FirstName": "John",
"LastName": "Doe",
"Age": 43,
"Address": {
"Street": "Downing Street 10",
"City": "London",
"Country": "Great Britain"
},
"Phone numbers": [
"+44 1234567",
"+44 2345678"
]
}
\endcode
The above example consists of an object with 5 key/value pairs. Two of the values are strings,
one is a number, one is another object and the last one an array.
A valid JSON document can contain either an array or an object, so a document always starts
with a square or curly bracket.
The JSON support in Qt consists of a set of 4 classes.
\section1 The JSON Classes
The JSON support in Qt consists of these classes:
\annotatedlist json
All JSON classes are value based, implicitly shared classes.
*/
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