QJsonObject 類

QJsonObject 類封裝 JSON 對象。 更多...

頭：	#include <QJsonObject>
CMake:	find_package(Qt6 REQUIRED COMPONENTS Core) target_link_libraries(mytarget PRIVATE Qt6::Core)
qmake:	QT += core

• 所有成員列錶，包括繼承成員
• QJsonObject is part of 在 Qt 中支持 JSON and 隱式共享類 .

此類 相等可比較 .

此類 相等可比較 with QJsonValue and QJsonValueConstRef.

注意： 此類的所有函數 可重入 .

公共類型

class	const_iterator
class	iterator
	ConstIterator
	Iterator
	key_type
	mapped_type
	size_type

公共函數

	QJsonObject ()
	QJsonObject (std::initializer_list<std::pair<QString, QJsonValue>> args )
	QJsonObject (const QJsonObject & other )
	QJsonObject (QJsonObject && other )
	~QJsonObject ()
QJsonObject::iterator	begin ()
QJsonObject::const_iterator	begin () const
QJsonObject::const_iterator	constBegin () const
QJsonObject::const_iterator	constEnd () const
QJsonObject::const_iterator	constFind (const QString & key ) const
QJsonObject::const_iterator	constFind (QLatin1StringView key ) const
QJsonObject::const_iterator	constFind (QStringView key ) const
bool	contains (const QString & key ) const
bool	contains (QLatin1StringView key ) const
bool	contains (QStringView key ) const
qsizetype	count () const
bool	empty () const
QJsonObject::iterator	end ()
QJsonObject::const_iterator	end () const
QJsonObject::iterator	erase (QJsonObject::iterator it )
QJsonObject::iterator	find (const QString & key )
QJsonObject::iterator	find (QLatin1StringView key )
QJsonObject::iterator	find (QStringView key )
QJsonObject::const_iterator	find (QLatin1StringView key ) const
QJsonObject::const_iterator	find (QStringView key ) const
QJsonObject::const_iterator	find (const QString & key ) const
QJsonObject::iterator	insert (const QString & key , const QJsonValue & value )
QJsonObject::iterator	insert (QLatin1StringView key , const QJsonValue & value )
QJsonObject::iterator	insert (QStringView key , const QJsonValue & value )
bool	isEmpty () const
QStringList	keys () const
qsizetype	length () const
void	remove (const QString & key )
void	remove (QLatin1StringView key )
void	remove (QStringView key )
qsizetype	size () const
void	swap (QJsonObject & other )
QJsonValue	take (const QString & key )
QJsonValue	take (QLatin1StringView key )
QJsonValue	take (QStringView key )
QVariantHash	toVariantHash () const
QVariantMap	toVariantMap () const
QJsonValue	value (const QString & key ) const
QJsonValue	value (QLatin1StringView key ) const
QJsonValue	value (QStringView key ) const
QJsonObject &	operator= (QJsonObject && other )
QJsonObject &	operator= (const QJsonObject & other )
QJsonValueRef	operator[] (const QString & key )
QJsonValue	operator[] (const QString & key ) const
QJsonValueRef	operator[] (QLatin1StringView key )
QJsonValueRef	operator[] (QStringView key )
QJsonValue	operator[] (QLatin1StringView key ) const
QJsonValue	operator[] (QStringView key ) const

靜態公共成員

QJsonObject	fromVariantHash (const QVariantHash & hash )
QJsonObject	fromVariantMap (const QVariantMap & map )

相關非成員

bool	operator!= (const QJsonObject & lhs , const QJsonObject & rhs )
bool	operator== (const QJsonObject & lhs , const QJsonObject & rhs )

詳細描述

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 QVariantMap . You can query the number of (key, value) pairs with size (), insert ()，和 remove () entries from it and iterate over its content using the standard C++ iterator pattern.

QJsonObject is an implicitly shared class, and shares the data with the document it has been created from as long as it is not being modified.

You can convert the object to and from text based JSON through QJsonDocument .

另請參閱 在 Qt 中支持 JSON and 保存和加載遊戲 .

成員類型文檔編製

QJsonObject:: ConstIterator

Qt 樣式同義詞 QJsonObject::const_iterator .

QJsonObject:: Iterator

Qt 樣式同義詞 QJsonObject::iterator .

QJsonObject:: key_type

typedef 對於 QString . Provided for STL compatibility.

QJsonObject:: mapped_type

typedef 對於 QJsonValue . Provided for STL compatibility.

QJsonObject:: size_type

Typedef for qsizetype. Provided for STL compatibility.

成員函數文檔編製

QJsonObject:: QJsonObject ()

構造空的 JSON 對象。

另請參閱 isEmpty ().

QJsonObject:: QJsonObject ( std::initializer_list < std::pair < QString , QJsonValue >> args )

Constructs a QJsonObject instance initialized from args initialization list. For example:

QJsonObject object
{
    {"property1", 1},
    {"property2", 2}
};
					

[noexcept] QJsonObject:: QJsonObject (const QJsonObject & other )

創建副本為 other .

Since QJsonObject is implicitly shared, the copy is shallow as long as the object does not get modified.

[noexcept] QJsonObject:: QJsonObject ( QJsonObject && other )

移動構造 QJsonObject，從 other .

[noexcept] QJsonObject:: ~QJsonObject ()

銷毀對象。

QJsonObject::iterator QJsonObject:: begin ()

返迴 STL 樣式迭代器 pointing to the first item in the object.

另請參閱 constBegin () 和 end ().

QJsonObject::const_iterator QJsonObject:: begin () const

這是重載函數。

QJsonObject::const_iterator QJsonObject:: constBegin () const

返迴常量 STL 樣式迭代器 pointing to the first item in the object.

另請參閱 begin () 和 constEnd ().

QJsonObject::const_iterator QJsonObject:: constEnd () const

返迴常量 STL 樣式迭代器 pointing to the imaginary item after the last item in the object.

另請參閱 constBegin () 和 end ().

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

Returns a const iterator pointing to the item with key key in the map.

If the map contains no item with key key ，函數返迴 constEnd ().

QJsonObject::const_iterator QJsonObject:: constFind ( QLatin1StringView key ) const

這是重載函數。

QJsonObject::const_iterator QJsonObject:: constFind ( QStringView key ) const

這是重載函數。

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

返迴 true if the object contains key key .

另請參閱 insert (), remove ()，和 take ().

bool QJsonObject:: contains ( QLatin1StringView key ) const

這是重載函數。

bool QJsonObject:: contains ( QStringView key ) const

這是重載函數。

qsizetype QJsonObject:: count () const

這是重載函數。

如同 size ().

bool QJsonObject:: empty () const

此函數為兼容 STL (標準模闆庫) 提供。它相當於 isEmpty (), returning true if the object is empty; otherwise returning false .

QJsonObject::iterator QJsonObject:: end ()

返迴 STL 樣式迭代器 pointing to the imaginary item after the last item in the object.

另請參閱 begin () 和 constEnd ().

QJsonObject::const_iterator QJsonObject:: end () const

這是重載函數。

QJsonObject::iterator QJsonObject:: erase ( QJsonObject::iterator it )

Removes the (key, value) pair pointed to by the iterator it from the map, and returns an iterator to the next item in the map.

另請參閱 remove ().

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

Returns an iterator pointing to the item with key key in the map.

If the map contains no item with key key ，函數返迴 end ().

QJsonObject::iterator QJsonObject:: find ( QLatin1StringView key )

這是重載函數。

QJsonObject::iterator QJsonObject:: find ( QStringView key )

這是重載函數。

QJsonObject::const_iterator QJsonObject:: find ( QLatin1StringView key ) const

這是重載函數。

QJsonObject::const_iterator QJsonObject:: find ( QStringView key ) const

這是重載函數。

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

這是重載函數。

[static] QJsonObject QJsonObject:: fromVariantHash (const QVariantHash & hash )

Converts the variant hash hash 到 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.

注意： Conversion from QVariant is not completely lossless. Please see the documentation in QJsonValue::fromVariant () 瞭解更多信息。

另請參閱 fromVariantMap (), toVariantHash ()，和 QJsonValue::fromVariant ().

[static] QJsonObject QJsonObject:: fromVariantMap (const QVariantMap & map )

Converts the variant map map 到 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.

注意： Conversion from QVariant is not completely lossless. Please see the documentation in QJsonValue::fromVariant () 瞭解更多信息。

另請參閱 fromVariantHash (), toVariantMap ()，和 QJsonValue::fromVariant ().

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

Inserts a new item with the key key 和值 value .

If there is already an item with the key key , then that item's value is replaced with value .

Returns an iterator pointing to the inserted item.

If the value is QJsonValue::Undefined , it will cause the key to get removed from the object. The returned iterator will then point to end ().

另請參閱 remove (), take (), QJsonObject::iterator ，和 end ().

QJsonObject::iterator QJsonObject:: insert ( QLatin1StringView key , const QJsonValue & value )

這是重載函數。

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

這是重載函數。

bool QJsonObject:: isEmpty () const

返迴 true if the object is empty. This is the same as size () == 0.

另請參閱 size ().

QStringList QJsonObject:: keys () const

返迴在此對象中的所有鍵列錶。

The list is sorted alphabetically.

qsizetype QJsonObject:: length () const

這是重載函數。

如同 size ().

void QJsonObject:: remove (const QString & key )

移除 key 從對象。

另請參閱 insert () 和 take ().

void QJsonObject:: remove ( QLatin1StringView key )

這是重載函數。

void QJsonObject:: remove ( QStringView key )

這是重載函數。

qsizetype QJsonObject:: size () const

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

[noexcept] void QJsonObject:: swap ( QJsonObject & other )

Swaps this object with other 。此操作很快且從不失敗。

QJsonValue QJsonObject:: take (const QString & key )

移除 key 從對象。

返迴 QJsonValue containing the value referenced by key 。若 key was not contained in the object, the returned QJsonValue is QJsonValue::Undefined .

另請參閱 insert (), remove ()，和 QJsonValue .

QJsonValue QJsonObject:: take ( QLatin1StringView key )

這是重載函數。

QJsonValue QJsonObject:: take ( QStringView key )

這是重載函數。

QVariantHash QJsonObject:: toVariantHash () const

把此對象轉換成 QVariantHash .

返迴創建的哈希。

另請參閱 toVariantMap ().

QVariantMap QJsonObject:: toVariantMap () const

把此對象轉換成 QVariantMap .

返迴創建的映射。

另請參閱 toVariantHash ().

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

返迴 QJsonValue 錶示值為鍵 key .

返迴的 QJsonValue is QJsonValue::Undefined 若鍵不存在。

另請參閱 QJsonValue and QJsonValue::isUndefined ().

QJsonValue QJsonObject:: value ( QLatin1StringView key ) const

這是重載函數。

QJsonValue QJsonObject:: value ( QStringView key ) const

這是重載函數。

[noexcept] QJsonObject &QJsonObject:: operator= ( QJsonObject && other )

移動賦值 other 到此對象。

[noexcept] QJsonObject &QJsonObject:: operator= (const QJsonObject & other )

賦值 other 到此對象。

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

Returns a reference to the value for key . If there is no value with key key in the object, one is created with a QJsonValue::Null value and then returned.

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.

另請參閱 value ().

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

返迴 QJsonValue 錶示值為鍵 key .

This does the same as value ().

返迴的 QJsonValue is QJsonValue::Undefined 若鍵不存在。

另請參閱 value (), QJsonValue ，和 QJsonValue::isUndefined ().

QJsonValueRef QJsonObject:: operator[] ( QLatin1StringView key )

這是重載函數。

QJsonValueRef QJsonObject:: operator[] ( QStringView key )

這是重載函數。

QJsonValue QJsonObject:: operator[] ( QLatin1StringView key ) const

這是重載函數。

QJsonValue QJsonObject:: operator[] ( QStringView key ) const

這是重載函數。

相關非成員

[noexcept] bool operator!= (const QJsonObject & lhs , const QJsonObject & rhs )

返迴 true if lhs object is not equal to rhs , false 否則。

[noexcept] bool operator== (const QJsonObject & lhs , const QJsonObject & rhs )

返迴 true if lhs 對象等於 rhs , false 否則。

內容

1. 公共類型

2. 公共函數

3. 靜態公共成員

4. 相關非成員

5. 詳細描述