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// Copyright (C) 2022 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
/*!
\example serialization/convert
\title Convert Example
\brief The Convert example demonstrates how to convert between different
serialization formats.
The Convert example converts between the serialization formats JSON, CBOR,
XML, QDataStream and text. It can also auto detect the format being used.
Not all formats support both input and output, and they have different
sets of which types they support. QDataStream and XML are the richest,
followed by CBOR, then JSON, and then the plain text one.
\image convert.png
\section1 The Converter Class
The Converter class is the abstract superclass for all the converters to
and from all the formats. They all convert to and from the QVariant class,
which is used to represent all the datastructures internally.
The name() function returns the name of the converter. The directions()
function is used to determine if a converter can be used for input, output,
or both. The outputOptions() and optionsHelp() functions are used to get
and query which options are used by the different converters. The
probeFile() function is used to determine if a file has the same file
format as the converter. The loadFile() function deserializes the given
file, while the saveFile() serializes to the given file.
\section1 The CborConverter Class
The CborConverter class shows how to serialize to and from the CBOR-format.
There is also a CborDiagnosticDumper class to output in CBOR diagnostic
notation. That is similar to JSON, but not exactly, because it allows
displaying the contents of a CBOR stream losslessly, while a conversion
to JSON is lossy.
The convertCborValue() function is used to convert a QCborValue to a
QVariant. It uses the helper functions convertCborMap() and
convertCborArray().
\snippet serialization/convert/cborconverter.cpp 0
A CBOR-file is read using loadFile() function.
\snippet serialization/convert/cborconverter.cpp 2
The convertFromVariant() function is used to convert a QVariant to a
QCborValue.
\snippet serialization/convert/cborconverter.cpp 1
A CBOR-file is written using the saveFile() function.
\snippet serialization/convert/cborconverter.cpp 3
\snippet serialization/convert/cborconverter.cpp 4
\sa {CBOR Support in Qt}
\section1 The DataStreamConverter Class
The DataStreamConverter class is used to serialize to and from the
QDataStream format. There is also the DataStreamDumper class for outputting
the data lossless in a non-standardized human readable format.
\section1 The JsonConverter Class
The JsonConverter class is used to serialize to and from the JSON-format.
\sa {JSON Support in Qt}
\section1 The XmlConverter Class
The XmlConverter class is used to serialize to and from the XML-format.
\section1 The TextConverter Class
The TextConverter class is used to serialize to and from a text format.
\section1 The NullConverter Class
The NullConverter class is an output serializer that does nothing.
*/
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