\inmodule QtCore\reentrant More...

#include <qjsonobject.h>

Collaboration diagram for QJsonObject::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 QJsonValueRef	reference

typedef QJsonValueRef *	pointer

Public Member Functions
	iterator ()
	Constructs an uninitialized iterator.

	iterator (QJsonObject *obj, qsizetype index)

constexpr	iterator (const iterator &other)=default

iterator &	operator= (const iterator &other)

QString	key () const
	Returns the current item's key.

QJsonValueRef	value () const
	Returns a modifiable reference to the current item's value.

QJsonValueRef	operator* () const
	Returns a modifiable reference to the current item's value.

const QJsonValueConstRef *	operator-> () const
	Returns a pointer to a constant reference to the current item.

QJsonValueRef *	operator-> ()
	Returns a pointer to a modifiable reference to the current item.

QJsonValueRef	operator[] (qsizetype j) const
	Returns a modifiable reference to the item at offset j from the item pointed to by this iterator (the item at position {*this + j}).

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.

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.

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

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.

iterator	operator+ (qsizetype j) const
	Returns an iterator to the item at j positions forward from this iterator.

iterator	operator- (qsizetype j) const
	Returns an iterator to the item at j positions backward from this iterator.

iterator &	operator+= (qsizetype j)
	Advances the iterator by j items.

iterator &	operator-= (qsizetype j)
	Makes the iterator go back by j items.

qsizetype	operator- (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	const_iterator

class	QJsonObject

bool	comparesEqual (const iterator &lhs, const iterator &rhs) noexcept

Qt::strong_ordering	compareThreeWay (const iterator &lhs, const iterator &rhs) noexcept

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

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

Detailed Description

\inmodule QtCore

\reentrant

Since: 5.0

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

\compares strong \compareswith strong QJsonObject::const_iterator \endcompareswith

QJsonObject::iterator allows you to iterate over a QJsonObject and to modify the value (but not the key) stored under a particular key. If you want to iterate over a const QJsonObject, you should use QJsonObject::const_iterator. 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::iterator constructor creates an uninitialized iterator. You must initialize it using a QJsonObject function like QJsonObject::begin(), QJsonObject::end(), or QJsonObject::find() before you can start iterating.

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

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

Definition at line 81 of file qjsonobject.h.

Member Typedef Documentation

◆ difference_type

QJsonObject::iterator::difference_type

Definition at line 89 of file qjsonobject.h.

◆ iterator_category

QJsonObject::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 88 of file qjsonobject.h.

◆ pointer

QJsonObject::iterator::pointer

Definition at line 92 of file qjsonobject.h.

◆ reference

QJsonObject::iterator::reference

Definition at line 91 of file qjsonobject.h.

◆ value_type

QJsonObject::iterator::value_type

Definition at line 90 of file qjsonobject.h.

Constructor & Destructor Documentation

◆ iterator() [1/3]

QJsonObject::iterator::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::begin(), QJsonObject::end()

Definition at line 94 of file qjsonobject.h.

◆ iterator() [2/3]

QJsonObject::iterator::iterator	(	QJsonObject *	obj,
		qsizetype	index )

inline

Definition at line 95 of file qjsonobject.h.

◆ iterator() [3/3]

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

constexprdefault

Member Function Documentation

◆ key()

QString QJsonObject::iterator::key ( ) const

inline

Returns the current item's key.

There is no direct way of changing an item's key through an iterator, although it can be done by calling QJsonObject::erase() followed by QJsonObject::insert().

See also: value()

Definition at line 104 of file qjsonobject.h.

References item.

◆ operator*()

QJsonValueRef QJsonObject::iterator::operator* ( ) const

inline

Returns a modifiable reference to the current item's value.

Same as value().

The return value is of type QJsonValueRef, a helper class for QJsonArray and QJsonObject. When you get an object of type QJsonValueRef, you can use it as if it were a reference to a QJsonValue. If you assign to it, the assignment will apply to the element in the QJsonArray or QJsonObject from which you got the reference.

See also: key()

Definition at line 106 of file qjsonobject.h.

References item.

◆ operator+()

QJsonObject::iterator QJsonObject::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.

See also: operator-()

Definition at line 125 of file qjsonobject.h.

References j.

◆ operator++() [1/2]

QJsonObject::iterator QJsonObject::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 121 of file qjsonobject.h.

References item.

◆ operator++() [2/2]

QJsonObject::iterator QJsonObject::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 122 of file qjsonobject.h.

References item.

◆ operator+=()

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

inline

Advances the iterator by j items.

If j is negative, the iterator goes backward.

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

Definition at line 127 of file qjsonobject.h.

References item, and j.

◆ operator-() [1/2]

qsizetype QJsonObject::iterator::operator- ( 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 129 of file qjsonobject.h.

References item, and j.

◆ operator-() [2/2]

QJsonObject::iterator QJsonObject::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.

See also: operator+()

Definition at line 126 of file qjsonobject.h.

References j, and operator+().

Here is the call graph for this function:

◆ operator--() [1/2]

QJsonObject::iterator QJsonObject::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 123 of file qjsonobject.h.

References item.

◆ operator--() [2/2]

QJsonObject::iterator QJsonObject::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 124 of file qjsonobject.h.

References item.

◆ operator-=()

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

inline

Makes the iterator go back by j items.

If j is negative, the iterator goes forward.

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

Definition at line 128 of file qjsonobject.h.

References item, and j.

◆ operator->() [1/2]

QJsonValueRef * QJsonObject::iterator::operator-> ( )

inline

Returns a pointer to a modifiable reference to the current item.

Definition at line 108 of file qjsonobject.h.

References item.

◆ operator->() [2/2]

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

inline

Returns a pointer to a constant reference to the current item.

Definition at line 107 of file qjsonobject.h.

References item.

◆ operator=()

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

inline

Definition at line 98 of file qjsonobject.h.

References item, and other().

Here is the call graph for this function:

◆ operator[]()

const QJsonValueRef QJsonObject::iterator::operator[] ( qsizetype j ) const

inline

Returns a modifiable reference to 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.

The return value is of type QJsonValueRef, a helper class for QJsonArray and QJsonObject. When you get an object of type QJsonValueRef, you can use it as if it were a reference to a QJsonValue. If you assign to it, the assignment will apply to the element in the QJsonArray or QJsonObject from which you got the reference.

See also: operator+()

Definition at line 109 of file qjsonobject.h.

References j.

◆ value()

QJsonValueRef QJsonObject::iterator::value ( ) const

inline

Returns a modifiable reference to the current item's value.

You can change the value of an item by using value() on the left side of an assignment.

The return value is of type QJsonValueRef, a helper class for QJsonArray and QJsonObject. When you get an object of type QJsonValueRef, you can use it as if it were a reference to a QJsonValue. If you assign to it, the assignment will apply to the element in the QJsonArray or QJsonObject from which you got the reference.

See also: key(), operator*()

Definition at line 105 of file qjsonobject.h.

References item.

Friends And Related Symbol Documentation

◆ comparesEqual [1/2]

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

friend

Definition at line 179 of file qjsonobject.h.

◆ comparesEqual [2/2]

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

friend

Definition at line 168 of file qjsonobject.h.

◆ compareThreeWay [1/2]

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

friend

Definition at line 183 of file qjsonobject.h.

◆ compareThreeWay [2/2]

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

friend

Definition at line 172 of file qjsonobject.h.

◆ const_iterator

friend class const_iterator

friend

Definition at line 83 of file qjsonobject.h.

◆ QJsonObject

friend class QJsonObject

friend

Definition at line 84 of file qjsonobject.h.

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

qtbase/src/corelib/serialization/qjsonobject.h (de2a467a77f338d4b1e0a5044b809bdaf413ca72)
qtbase/src/corelib/serialization/qjsonobject.cpp (de2a467a77f338d4b1e0a5044b809bdaf413ca72)

Public Types

Public Member Functions

Friends

Detailed Description

Member Typedef Documentation

◆ difference_type

◆ iterator_category

◆ pointer

◆ reference

◆ value_type

Constructor & Destructor Documentation

◆ iterator() [1/3]

◆ iterator() [2/3]

◆ iterator() [3/3]

Member Function Documentation

◆ key()

◆ operator*()

◆ operator+()

◆ operator++() [1/2]

◆ operator++() [2/2]

◆ operator+=()

◆ operator-() [1/2]

◆ operator-() [2/2]

◆ operator--() [1/2]

◆ operator--() [2/2]

◆ operator-=()

◆ operator->() [1/2]

◆ operator->() [2/2]

◆ operator=()

◆ operator[]()

◆ value()

Friends And Related Symbol Documentation

◆ comparesEqual [1/2]

◆ comparesEqual [2/2]

◆ compareThreeWay [1/2]

◆ compareThreeWay [2/2]

◆ const_iterator

◆ QJsonObject