The QJsonObject class encapsulates a JSON object. More...

Public Typedefs
using	const_iterator = QFlatMap< QString, QJsonValue >::const_iterator

using	iterator = QFlatMap< QString, QJsonValue >::iterator

using	key_type = QString

using	mapped_type = QJsonValue

using	size_type = QFlatMap< QString, QJsonValue >::size_type

Public Methods
	QJsonObject ()

	QJsonObject (const QJsonObject &other)

	QJsonObject (const_iterator iter_begin, const_iterator iter_end)

	QJsonObject (QJsonObject &&other)

	QJsonObject (std::initializer_list< QPair< QString, QJsonValue >> list)

	~QJsonObject ()

iterator	begin ()

const_iterator	begin () const

const_iterator	constBegin () const

const_iterator	constEnd () const

const_iterator	constFind (const QString &key) const

bool	contains (const QString &key) const

int	count () const

bool	empty () const

iterator	end ()

const_iterator	end () const

iterator	erase (const_iterator iter)

iterator	find (const QString &key)

const_iterator	find (const QString &key) const

iterator	insert (const QString &key, QJsonValue value)

bool	isEmpty () const

QStringList	keys () const

int	length () const

bool	operator!= (const QJsonObject &other) const

QJsonObject &	operator= (const QJsonObject &other)

bool	operator== (const QJsonObject &other) const

QJsonValue &	operator[] (const QString &key)

const QJsonValue &	operator[] (const QString &key) const

void	remove (const QString &key)

size_type	size () const

QJsonValue	take (const QString &key)

QVariantHash	toVariantHash () const

QVariantMap	toVariantMap () const

const QJsonValue &	value (const QString &key) const

Static Public Methods
static QJsonObject	fromVariantHash (const QVariantHash &hash)

static QJsonObject	fromVariantMap (const QVariantMap &map)

Friends
class	QJsonValue

Detailed Description

The QJsonObject class encapsulates a JSON object. A JSON object is a list of key value pairs where the keys are unique strings and the values are represented by a QJsonValue.

A QJsonObject can be converted to and from a QVariantHash or a QVariantMap. You can query the number of (key, value) pairs with size(), insert(), and remove() entries from it and iterate over its content using the standard C++ iterator pattern.

The object can be converted to and from a text based JSON format through QJsonDocument.

QJsonObject object1;
object1.insert("tabSpacing",   3);
object1.insert("useSpaces",    true);
 
 
/* to json */
 
// create document
QJsonDocument doc1(object1);
 
// save data to QByteArray
QByteArray data = doc.toJson();
 
// data can be saved to a file at this point
 
 
/* from json */
 
// load data from QByteArray
QJsonDocument doc2 = QJsonDocument::fromJson(data);
 
// retrieve json object
QJsonObject object2 = doc2.object();

See also: JSON Support

Member Typedef Documentation

QJsonObject::const_iterator

Typedef for QFlatMap<QString, QJsonValue>::const_iterator.

See also: QFlatMap::const_iterator

QJsonObject::iterator

Typedef for QFlatMap<QString, QJsonValue>::iterator.

See also: QFlatMap::iterator

QJsonObject::key_type

Typedef for QString.

QJsonObject::mapped_type

Typedef for QJsonValue.

QJsonObject::size_type

Typedef for int.

Constructor & Destructor Documentation

QJsonObject::QJsonObject ( )

Constructs an empty JSON object.

See also: isEmpty()

QJsonObject::QJsonObject	(	const_iterator	iter_begin,
		const_iterator	iter_end
	)

Constructs a QJsonArray using an iterator range.

QJsonObject::QJsonObject ( std::initializer_list< QPair< QString, QJsonValue >> list )

Constructs a QJsonObject initialized from list.

QJsonObject object
{
    {"key_A", 1},
    {"key_B", 2}
};

QJsonObject::QJsonObject ( const QJsonObject & other )

Copy constructs a new QJsonObject from other.

QJsonObject::QJsonObject ( QJsonObject && other )

Move constructs a new QJsonObject from other.

QJsonObject::~QJsonObject ( )

Destroys this object.

Method Documentation

iterator QJsonObject::begin ( )

Returns an STL-style iterator pointing to the first item in the object.

See also: constBegin(), end()

const_iterator QJsonObject::begin ( ) const

Returns an STL-style const iterator pointing to the first item in the object.

const_iterator QJsonObject::constBegin ( ) const

Returns a const STL-style const iterator pointing to the first item in the object.

See also: begin(), constEnd()

const_iterator QJsonObject::constEnd ( ) const

Returns a const STL-style iterator pointing to the imaginary item after the last item in the object.

See also: constBegin(), end()

const_iterator QJsonObject::constFind ( const QString & key ) const

Returns a const iterator pointing to the item with the given key. If the object contains no item with key, returns end.

bool QJsonObject::contains ( const QString & key ) const

Returns true if the object contains the given key.

See also: insert(), remove(), take()

int QJsonObject::count ( ) const

inline

Equivalent to calling size().

bool QJsonObject::empty ( ) const

inline

Equivalent to isEmpty(), returning true if the object is empty, otherwise returning false.

iterator QJsonObject::end ( )

Returns an STL-style iterator pointing to the imaginary item after the last item in the object.

See also: begin(), constEnd()

const_iterator QJsonObject::end ( ) const

Returns an STL-style const iterator pointing to the imaginary item after the last item in the object.

iterator QJsonObject::erase ( const_iterator iter )

Removes the (key, value) pair pointed to by the iterator iter, Returns an iterator to the next item in the object.

QJsonObject::const_iterator iter = object.find("someKey");

object.erase(iter);

See also: remove()

iterator QJsonObject::find ( const QString & key )

Returns an iterator pointing to the item with the given key. If the object contains no item with key, returns end.

const_iterator QJsonObject::find ( const QString & key ) const

inline

Returns a const iterator pointing to the item with the given key. If the object contains no item with key, returns end.

QJsonObject QJsonObject::fromVariantHash ( const QVariantHash & hash )

static

Converts the variant hash to a QJsonObject. The keys in hash will be used as the keys in the JSON object and the QVariant values will be converted to JSON values.

See also: toVariantHash(), QJsonValue::fromVariant()

QJsonObject QJsonObject::fromVariantMap ( const QVariantMap & map )

static

Converts the variant map to a QJsonObject. The keys in map will be used as the keys in the JSON object and the QVariant values will be converted to JSON values.

See also: toVariantMap(), QJsonValue::fromVariant()

iterator QJsonObject::insert	(	const QString &	key,
		QJsonValue	value
	)

Inserts a new item with the string key and a JsonValue of value. If there is already an item with the key the item's value is replaced with the new value. Returns an iterator pointing to the inserted item.

If the value is QJsonValue::Undefined the key will be removed from the object. The returned iterator points to end().

See also: remove(), take(), QJsonObject::iterator, end()

bool QJsonObject::isEmpty ( ) const

Returns true if the object is empty. Equivalent to calling size() == 0.

See also: empty(), size()

QStringList QJsonObject::keys ( ) const

Returns a list of all keys in this object.

int QJsonObject::length ( ) const

inline

Equivalent to calling size().

bool QJsonObject::operator!= ( const QJsonObject & other ) const

Returns true if other is not equal to this object.

QJsonObject & QJsonObject::operator= ( const QJsonObject & other )

Copy assigns from other and returns a reference to this object.

bool QJsonObject::operator== ( const QJsonObject & other ) const

Returns true if other is equal to this object.

QJsonValue & QJsonObject::operator[] ( const QString & key )

Returns a reference to the value for key. The return value is of type QJsonValue.

See also: value()

const QJsonValue & QJsonObject::operator[] ( const QString & key ) const

Returns a QJsonValue representing the value the given key. Equivalent to calling value(). The returned QJsonValue is QJsonValue::Undefined if the key does not exist.

See also: value(), QJsonValue, QJsonValue::isUndefined()

void QJsonObject::remove ( const QString & key )

Removes the (key, value) pair corresponding to the given key.

See also: erase(), insert(), take()

size_type QJsonObject::size ( ) const

Returns the number of (key, value) pairs stored in this object.

QJsonValue QJsonObject::take ( const QString & key )

Removes key from the object. Returns a QJsonValue containing the value referenced by key. If key was not contained in the object the returned QJsonValue is QJsonValue::Undefined().

See also: insert(), remove(), QJsonValue

QVariantHash QJsonObject::toVariantHash ( ) const

Converts this object to a QVariantHash. Returns the created hash.

QVariantMap QJsonObject::toVariantMap ( ) const

Converts this object to a QVariantMap. Returns the created map.

const QJsonValue & QJsonObject::value ( const QString & key ) const

Returns a QJsonValue representing the value for the given key. The returned QJsonValue is QJsonValue::Undefined if the key does not exist.

See also: QJsonValue, QJsonValue::isUndefined()

Public Typedefs

Public Methods

Static Public Methods

Friends

Detailed Description

Member Typedef Documentation

Constructor & Destructor Documentation

Method Documentation