\inmodule QtCore More...

#include <qjsonobject.h>

Collaboration diagram for QJsonObject::const_iterator:

Public Types
typedef std::random_access_iterator_tag	iterator_category
	A synonym for {std::random_access_iterator_tag} indicating this iterator is a random-access iterator.
typedef qsizetype	difference_type
typedef QJsonValue	value_type
typedef const QJsonValueConstRef	reference
typedef const QJsonValueConstRef *	pointer

Public Member Functions
	const_iterator ()
	Constructs an uninitialized iterator.
	const_iterator (const QJsonObject *obj, qsizetype index)
	const_iterator (const iterator &other)
	Constructs a copy of other.
constexpr	const_iterator (const const_iterator &other)=default
const_iterator &	operator= (const const_iterator &other)
QString	key () const
	Returns the current item's key.
QAnyStringView	keyView () const
QJsonValueConstRef	value () const
	Returns the current item's value.
const QJsonValueConstRef	operator* () const
	Returns the current item's value.
const QJsonValueConstRef *	operator-> () const
	Returns a pointer to the current item.
QJsonValueConstRef	operator[] (qsizetype j) const
	Returns the item at offset j from the item pointed to by this iterator (the item at position {*this + j}).
const_iterator &	operator++ ()
	The prefix {++} operator, {++i}, advances the iterator to the next item in the object and returns an iterator to the new current item.
const_iterator	operator++ (int)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.The postfix {++} operator, {i++}, advances the iterator to the next item in the object and returns an iterator to the previously current item.
const_iterator &	operator-- ()
	The prefix {–} operator, {–i}, makes the preceding item current and returns an iterator pointing to the new current item.
const_iterator	operator-- (int)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.The postfix {–} operator, {i–}, makes the preceding item current and returns an iterator pointing to the previously current item.
const_iterator	operator+ (qsizetype j) const
	Returns an iterator to the item at j positions forward from this iterator.
const_iterator	operator- (qsizetype j) const
	Returns an iterator to the item at j positions backward from this iterator.
const_iterator &	operator+= (qsizetype j)
	Advances the iterator by j items.
const_iterator &	operator-= (qsizetype j)
	Makes the iterator go back by j items.
qsizetype	operator- (const_iterator j) const
	Returns the number of items between the item pointed to by other and the item pointed to by this iterator.

Friends
class	iterator
bool	comparesEqual (const const_iterator &lhs, const const_iterator &rhs) noexcept
Qt::strong_ordering	compareThreeWay (const const_iterator &lhs, const const_iterator &rhs)

Detailed Description

\inmodule QtCore

Since: 5.0

The QJsonObject::const_iterator class provides an STL-style const iterator for QJsonObject.

\compares strong \compareswith strong QJsonObject::iterator \endcompareswith

QJsonObject::const_iterator allows you to iterate over a QJsonObject. If you want to modify the QJsonObject as you iterate over it, you must use QJsonObject::iterator instead. It is generally good practice to use QJsonObject::const_iterator on a non-const QJsonObject as well, unless you need to change the QJsonObject through the iterator. Const iterators are slightly faster and improve code readability.

The default QJsonObject::const_iterator constructor creates an uninitialized iterator. You must initialize it using a QJsonObject function like QJsonObject::constBegin(), QJsonObject::constEnd(), or QJsonObject::find() before you can start iterating.

Multiple iterators can be used on the same object. Existing iterators will however become dangling if the object gets modified.

See also: QJsonObject::iterator, {JSON Support in Qt}, {Saving and Loading a Game}

Definition at line 207 of file qjsonobject.h.

Member Typedef Documentation

◆ difference_type

typedef qsizetype QJsonObject::const_iterator::difference_type

Definition at line 214 of file qjsonobject.h.

◆ iterator_category

typedef std::random_access_iterator_tag QJsonObject::const_iterator::iterator_category

A synonym for {std::random_access_iterator_tag} indicating this iterator is a random-access iterator.

Note: In Qt versions before 5.6, this was set by mistake to {std::bidirectional_iterator_tag}.

Definition at line 213 of file qjsonobject.h.

◆ pointer

typedef const QJsonValueConstRef* QJsonObject::const_iterator::pointer

Definition at line 217 of file qjsonobject.h.

◆ reference

typedef const QJsonValueConstRef QJsonObject::const_iterator::reference

Definition at line 216 of file qjsonobject.h.

◆ value_type

typedef QJsonValue QJsonObject::const_iterator::value_type

Definition at line 215 of file qjsonobject.h.

Constructor & Destructor Documentation

◆ const_iterator() [1/4]

QJsonObject::const_iterator::const_iterator ( )

inline

Constructs an uninitialized iterator.

Functions like key(), value(), and operator++() must not be called on an uninitialized iterator. Use operator=() to assign a value to it before using it.

See also: QJsonObject::constBegin(), QJsonObject::constEnd()

Definition at line 219 of file qjsonobject.h.

◆ const_iterator() [2/4]

QJsonObject::const_iterator::const_iterator	(	const QJsonObject *	obj,
		qsizetype	index )

inline

Definition at line 220 of file qjsonobject.h.

◆ const_iterator() [3/4]

QJsonObject::const_iterator::const_iterator ( const iterator & other )

inline

Constructs a copy of other.

Definition at line 222 of file qjsonobject.h.

◆ const_iterator() [4/4]

QJsonObject::const_iterator::const_iterator ( const const_iterator & other )

constexprdefault

Member Function Documentation

◆ key()

QString QJsonObject::const_iterator::key ( ) const

inline

Returns the current item's key.

See also: value(), keyView()

Definition at line 232 of file qjsonobject.h.

◆ keyView()

QAnyStringView QJsonObject::const_iterator::keyView ( ) const

inline

Since: 6.10

Returns the current item's key as a QAnyStringView. This function does not allocate.

Since QJsonObject stores keys in US-ASCII, UTF-8 or UTF-16, the returned QAnyStringView may be in any of these encodings.

See also: value(), key()

Definition at line 233 of file qjsonobject.h.

◆ operator*()

const QJsonValueConstRef QJsonObject::const_iterator::operator* ( ) const

inline

Returns the current item's value.

Same as value().

See also: key(), keyView()

Definition at line 235 of file qjsonobject.h.

◆ operator+()

const_iterator QJsonObject::const_iterator::operator+ ( qsizetype j ) const

inline

Returns an iterator to the item at j positions forward from this iterator.

If j is negative, the iterator goes backward.

This operation can be slow for large j values.

See also: operator-()

Definition at line 253 of file qjsonobject.h.

◆ operator++() [1/2]

const_iterator & QJsonObject::const_iterator::operator++ ( )

inline

The prefix {++} operator, {++i}, advances the iterator to the next item in the object and returns an iterator to the new current item.

Calling this function on QJsonObject::end() leads to undefined results.

See also: operator--()

Definition at line 249 of file qjsonobject.h.

◆ operator++() [2/2]

const_iterator QJsonObject::const_iterator::operator++ ( int )

inline

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.The postfix {++} operator, {i++}, advances the iterator to the next item in the object and returns an iterator to the previously current item.

Definition at line 250 of file qjsonobject.h.

◆ operator+=()

const_iterator & QJsonObject::const_iterator::operator+= ( qsizetype j )

inline

Advances the iterator by j items.

If j is negative, the iterator goes backward.

This operation can be slow for large j values.

See also: operator-=(), operator+()

Definition at line 255 of file qjsonobject.h.

◆ operator-() [1/2]

qsizetype QJsonObject::const_iterator::operator- ( const_iterator j ) const

inline

Returns the number of items between the item pointed to by other and the item pointed to by this iterator.

Definition at line 257 of file qjsonobject.h.

◆ operator-() [2/2]

const_iterator QJsonObject::const_iterator::operator- ( qsizetype j ) const

inline

Returns an iterator to the item at j positions backward from this iterator.

If j is negative, the iterator goes forward.

This operation can be slow for large j values.

See also: operator+()

Definition at line 254 of file qjsonobject.h.

◆ operator--() [1/2]

const_iterator & QJsonObject::const_iterator::operator-- ( )

inline

The prefix {–} operator, {–i}, makes the preceding item current and returns an iterator pointing to the new current item.

Calling this function on QJsonObject::begin() leads to undefined results.

See also: operator++()

Definition at line 251 of file qjsonobject.h.

◆ operator--() [2/2]

const_iterator QJsonObject::const_iterator::operator-- ( int )

inline

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.The postfix {–} operator, {i–}, makes the preceding item current and returns an iterator pointing to the previously current item.

Definition at line 252 of file qjsonobject.h.

◆ operator-=()

const_iterator & QJsonObject::const_iterator::operator-= ( qsizetype j )

inline

Makes the iterator go back by j items.

If j is negative, the iterator goes forward.

This operation can be slow for large j values.

See also: operator+=(), operator-()

Definition at line 256 of file qjsonobject.h.

◆ operator->()

const QJsonValueConstRef * QJsonObject::const_iterator::operator-> ( ) const

inline

Returns a pointer to the current item.

Definition at line 236 of file qjsonobject.h.

◆ operator=()

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

inline

Definition at line 226 of file qjsonobject.h.

◆ operator[]()

QJsonValueConstRef QJsonObject::const_iterator::operator[] ( qsizetype j ) const

inline

Returns the item at offset j from the item pointed to by this iterator (the item at position {*this + j}).

This function is provided to make QJsonObject iterators behave like C++ pointers.

See also: operator+()

Definition at line 237 of file qjsonobject.h.

◆ value()

QJsonValueConstRef QJsonObject::const_iterator::value ( ) const

inline

Returns the current item's value.

See also: key(), keyView(), operator*()

Definition at line 234 of file qjsonobject.h.

◆ comparesEqual

bool comparesEqual	(	const const_iterator &	lhs,
		const const_iterator &	rhs )

friend

Definition at line 285 of file qjsonobject.h.

◆ compareThreeWay

Qt::strong_ordering compareThreeWay	(	const const_iterator &	lhs,
		const const_iterator &	rhs )

friend

Definition at line 289 of file qjsonobject.h.

◆ iterator

friend class iterator

friend

Definition at line 209 of file qjsonobject.h.

The documentation for this class was generated from the following files:

qtbase/src/corelib/serialization/qjsonobject.h (a3572dd5e8a27e6c308255ddcf05de4dc9036cdd)
qtbase/src/corelib/serialization/qjsonobject.cpp (cd4813a3c304a6d9d5d8096d91a8fc297818d624)

Public Types

Public Member Functions

Friends

Detailed Description

Member Typedef Documentation

◆ difference_type

◆ iterator_category

◆ pointer

◆ reference

◆ value_type

Constructor & Destructor Documentation

◆ const_iterator() [1/4]

◆ const_iterator() [2/4]

◆ const_iterator() [3/4]

◆ const_iterator() [4/4]

Member Function Documentation

◆ key()

◆ keyView()

◆ operator*()

◆ operator+()

◆ operator++() [1/2]

◆ operator++() [2/2]

◆ operator+=()

◆ operator-() [1/2]

◆ operator-() [2/2]

◆ operator--() [1/2]

◆ operator--() [2/2]

◆ operator-=()

◆ operator->()

◆ operator=()

◆ operator[]()

◆ value()

Friends And Related Symbol Documentation

◆ comparesEqual

◆ compareThreeWay

◆ iterator