88 lines
2.1 KiB
Plaintext
88 lines
2.1 KiB
Plaintext
/**
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\mainpage
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\section _intro Introduction
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<a HREF="http://www.json.org/">JSON (JavaScript Object Notation)</a>
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is a lightweight data-interchange format.
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It can represents integer, real number, string, an ordered sequence of value, and
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a collection of name/value pairs.
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QJson is a qt-based library that maps JSON data to QVariant objects.
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JSON arrays will be mapped to QVariantList instances, while JSON's objects will
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be mapped to QVariantMap.
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\section _usage Usage
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Converting JSON's data to QVariant instance is really simple:
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\code
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// create a JSonDriver instance
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QJson::Parser parser;
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bool ok;
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// json is a QString containing the data to convert
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QVariant result = parser.parse (json, &ok);
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\endcode
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Suppose you're going to convert this JSON data:
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\verbatim
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{
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"encoding" : "UTF-8",
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"plug-ins" : [
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"python",
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"c++",
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"ruby"
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],
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"indent" : { "length" : 3, "use_space" : true }
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}
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\endverbatim
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The following code would convert the JSON data and parse it:
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\code
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QJson::Parser parser;
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bool ok;
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QVariantMap result = parser.parse (json, &ok).toMap();
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if (!ok) {
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qFatal("An error occured during parsing");
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exit (1);
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}
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qDebug() << "encoding:" << result["encoding"].toString();
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qDebug() << "plugins:";
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foreach (QVariant plugin, result["plug-ins"].toList()) {
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qDebug() << "\t-" << plugin.toString();
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}
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QVariantMap nestedMap = result["indent"].toMap();
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qDebug() << "length:" << nestedMap["length"].toInt();
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qDebug() << "use_space:" << nestedMap["use_space"].toBool();
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\endcode
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The output would be:
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\verbatim
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encoding: "UTF-8"
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plugins:
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- "python"
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- "c++"
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- "ruby"
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length: 3
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use_space: true
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\endverbatim
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The QJson::QObjectHelper class permits to serialize QObject instances into JSON. QJson::QObjectHelper also allows to
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initialize a QObject using the values stored inside of a JSON object.
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\section _build Build instructions
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QJson build system is based on cmake. Download QJson sources, extract them, move inside the sources directory and then:
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\code
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mkdir build
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cd build
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cmake ..
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make
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sudo make install
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\endcode
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\author Flavio Castelli <flavio@castelli.name>
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*/
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